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SummaryGenes disrupted in schizophrenia may be revealed by de novo mutations in affected persons from otherwise healthy families. Furthermore, during normal brain development, genes are expressed in patterns specific to developmental stage and neuroanatomical structure. We identified de novo mutations in persons with schizophrenia and then mapped the responsible genes onto transcriptome profiles of normal human brain tissues from age 13 weeks gestation to adulthood. In the dorsolateral and ventrolateral prefrontal cortex during fetal development, genes harboring damaging de novo mutations in schizophrenia formed a network significantly enriched for transcriptional coexpression and protein interaction. The 50 genes in the network function in neuronal migration, synaptic transmission, signaling, transcriptional regulation, and transport. These results suggest that disruptions of fetal prefrontal cortical neurogenesis are critical to the pathophysiology of schizophrenia. These results also support the feasibility of integrating genomic and transcriptome analyses to map critical neurodevelopmental processes in time and space in the brain.

The Consortium on the Genetics of Schizophrenia has undertaken a large multisite study to characterize 12 neurophysiological and neurocognitive endophenotypic measures as a step toward understanding the complex genetic basis of schizophrenia. The authors previously demonstrated the heritability of these endophenotypes; in the present study, genetic linkage was evaluated.Each family consisted of a proband with schizophrenia, at least one unaffected sibling, and both parents. A total of 1,286 participants from 296 families were genotyped in two phases, and 1,004 individuals were also assessed for the endophenotypes. Linkage analyses of the 6,055 single-nucleotide polymorphisms that were successfully assayed, 5,760 of which were common to both phases, were conducted using both variance components and pedigree-wide regression methods.Linkage analyses of the 12 endophenotypes collectively identified one region meeting genome-wide significance criteria, with a LOD (log of odds) score of 4.0 on chromosome 3p14 for the antisaccade task, and another region on 1p36 nearly meeting genome-wide significance, with a LOD score of 3.5 for emotion recognition. Chromosomal regions meeting genome-wide suggestive criteria with LOD scores2.2 were identified for spatial processing (2p25 and 16q23), sensorimotor dexterity (2q24 and 2q32), prepulse inhibition (5p15), the California Verbal Learning Test (8q24), the degraded-stimulus Continuous Performance Test (10q26), face memory (10q26 and 12p12), and the Letter-Number Span (14q23).Twelve regions meeting genome-wide significant and suggestive criteria for previously identified heritable, schizophrenia-related endophenotypes were observed, and several genes of potential neurobiological interest were identified. Replication and further genomic studies are needed to assess the biological significance of these results.

Copy Number Variation (CNV) is increasingly implicated in disease pathogenesis. CNVs are often identified by statistical models applied to data from single nucleotide polymorphism (SNP) panels. Family information for samples provides additional information for CNV inference. Two modes of PennCNV (the Joint-call and Posterior-call), which are some of the most well-developed family-based CNV calling methods, use a “Joint-model” as a main component. This models all family members’ CNV states together with Mendelian inheritance. Methods based on the Joint-model are used to infer CNV calls of cases and controls in a pedigree, which may be compared to each other to test an association. Although benefits from the Joint-model have been shown elsewhere, equality of call rates in parents and offspring has not been evaluated previously. This can affect downstream analyses in studies that compare CNV rates in cases versus controls in pedigrees. In this paper, we show that the Joint-model can introduce different CNV call rates among family members in the absence of a true difference. First, we show that the Joint-model may analytically introduce differential CNV calls because of asymmetry of the model. We demonstrate these differential call rates using single-marker simulations. We show that call rates using the two modes of PennCNV also differ between parents-offspring in one multi-marker simulated dataset and two real datasets. Our results advise need for caution in use of the Joint-model calls in CNV association studies with family-based datasets.

Genes affecting glutamate neurotransmission featured prominently in associations between 94 genes and 12 inherited physiological or cognitive characteristics of schizophrenia. Of 16,620 possible SNP-trait associations, 47 showed strong significance.

Genetic studies of schizophrenia focus increasingly on putative endophenotypes because their genetic etiology may be simpler than clinical diagnosis. The Consortium on the Genetics of Schizophrenia (COGS), a multisite family study, aims to identify the genetic basis of several endophenotypes including verbal declarative memory (VDM), a neurocognitive function that shows robust impairment in schizophrenia. We present data on one type of measure of VDM, the California Verbal Learning Test, Second Edition (CVLT-II), in schizophrenia probands (n=305), their full biological siblings (n=449) and parents (n=232), and in community comparison subjects (CCS; n=509) across seven sites. Probands performed more poorly on each of five CVLT-II measures compared to related sibling and parent groups and CCS. Siblings and parents performed significantly worse than CCS on one measure (Discriminability), but with smaller effect sizes and less impairment than observed previously. The results raise questions about the homogeneity of VDM as an endophenotype, about methodological issues related to sampling, and about psychometric issues that impact the utility of the CVLT for detecting VDM deficits in nonpsychotic relatives of persons with schizophrenia.

Working memory (WM) impairment is a promising candidate endophenotype for schizophrenia that could facilitate the identification of susceptibility genes for this disorder. The validity of this putative endophenotype was assessed by determining whether 149 probands with schizophrenia and 337 of their first-degree relatives demonstrated WM impairment as compared to 190 unaffected community comparison subjects. Subjects were participants in the Consortium on the Genetics of Schizophrenia (COGS) project, a seven-site research network that was established to investigate the genetic architecture of endophenotypes for schizophrenia. Participants received comprehensive clinical assessments and completed two verbal WM tasks, one requiring transient on-line storage and another requiring maintenance plus complex manipulation of information by reordering the stimuli. Schizophrenia probands performed worse than the other groups on both tasks, with larger deficits found for the more challenging reordering WM task. The probands' relatives performed more poorly than community comparison subjects on both tasks, but the difference was significant only for the more challenging maintenance plus complex manipulation WM task. This WM impairment was not attributable to diagnoses of schizophrenia spectrum disorder, mood disorders, or substance use disorders in the relatives. In conjunction with evidence that WM abilities are substantially heritable, the current results support the validity and usefulness of verbal WM impairments in manipulation of information as endophenotypes for schizophrenia in large-scale genetic linkage and association studies.

© 2014. The impaired ability to make correct antisaccades (i.e., antisaccade performance) is well documented among schizophrenia subjects, and researchers have successfully demonstrated that antisaccade performance is a valid schizophrenia endophenotype that is useful for genetic studies. However, it is unclear how the ascertainment biases that unavoidably result from recruitment differences in schizophrenia subjects identified in family versus case-control studies may influence patient-control differences in antisaccade performance. To assess the impact of ascertainment bias, researchers from the Consortium on the Genetics of Schizophrenia (COGS) compared antisaccade performance and antisaccade metrics (latency and gain) in schizophrenia and control subjects from COGS-1, a family-based schizophrenia study, to schizophrenia and control subjects from COGS-2, a corresponding case-control study. COGS-2 schizophrenia subjects were substantially older; had lower education status, worse psychosocial function, and more severe symptoms; and were three times more likely to be a member of a multiplex family than COGS-1 schizophrenia subjects. Despite these variations, which were likely the result of ascertainment differences (as described in the introduction to this special issue), the effect sizes of the control-schizophrenia differences in antisaccade performance were similar in both studies (Cohen's d effect size of 1.06 and 1.01 in COGS-1 and COGS-2, respectively). This suggests that, in addition to the robust, state-independent schizophrenia-related deficits described in endophenotype studies, group differences in antisaccade performance do not vary based on subject ascertainment and recruitment factors.

Background: The Consortium on the Genetics of Schizophrenia (COGS) is an ongoing, National Institute of Mental Health–funded, 7-site collaboration investigating the occurrence and genetic architecture of quantitative endophenotypes related to schizophrenia. The purpose of this article is to provide a description of the COGS structure and methods, including participant recruitment and assessment. Methods: The hypothesis-driven recruitment strategy ascertains families that include a proband with a Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition diagnosis of schizophrenia, and at least one unaffected full sibling available for genotyping and endophenotyping, along with parents available for genotyping and (optional depending on age) endophenotyping. The family structure is selected to provide contrast in quantitative endophenotypic traits and thus to maximize the power of the planned genetic analyses. Probands are recruited from many sources including clinician referrals, local National Alliance for the Mentally Ill chapters, and advertising via the media. All participants undergo a standardized protocol that includes clinical characterization, a blood draw for genotyping, and endophenotype assessments (P50 suppression, prepulse inhibition, antisaccade performance, continuous performance tasks, letter-number span, verbal memory, and a computerized neurocognitive battery). Investigators participate in weekly teleconferences to coordinate and evaluate recruitment, clinical assessment, endophenotyping, and continuous quality control of data gathering and analyses. Data integrity is maintained through use of a highly quality-assured, centralized web-based database. Results: As of February 2006, 355 families have been enrolled and 688 participants have been endophenotyped, including schizophrenia probands (n = 154, M:F = 110:44), first-degree biological relatives (n = 343, M:F = 151:192), and community comparison subjects (n = 191, M:F = 81:110). Discussion: Successful multisite genetics collaborations must institute standardized methodological criteria for assessment and recruitment that are clearly defined, well communicated, and uniformly applied. In parallel, studies utilizing endophenotypes require strict adherence to criteria for cross-site data acquisition, equipment calibration and testing and software equivalence, and continuous quality assurance for many measures obtained across sites. This report describes methods and presents the structure of the COGS as a model of multisite endophenotype genetic studies. It also provides demographic information after the first 2 years of data collection on a sample for whom the behavioral data and genetics of endophenotype performance will be fully characterized in future articles. Some issues discussed in the reviews that follow reflect the challenges of evaluating endophenotypes in studies of the genetic architecture of endophenotypes in schizophrenia.

Women with posttraumatic stress disorder (PTSD) report poor health, but associations with health care utilization are understudied.To determine associations between medical/surgical utilization and PTSD in female Veterans Affairs (VA) patients.Prospective comparison of utilization rates between women screening positive or negative for PTSD on a mailed survey.Women receiving care at an urban VA medical center between October 1996 and January 2000.Survey responses, including a validated screen for PTSD (PCL-C), and VA utilization data through September 2002.Two thousand five hundred and seventy-eight (2,578) women (78% of those eligible) completed the PCL-C; 858 (33%) of them screened positive for PTSD (PTSD+). In unadjusted models, PTSD+ women had higher rates of medical/surgical hospitalizations and surgical inpatient procedures. Among women ages 35 to 49, mean days hospitalized/100 patients/year was 43.4 (95% CI 26 to 61) for PTSD+ women versus 17.0 (16 to 18) for PTSD negative (PTSD-) women. More PTSD+ women underwent surgical procedures (P.001). Mean annual outpatient visits were significantly higher among PTSD+ women, including: emergency department (ED) (1.1 [1.0 to 1.2] vs 0.6 [0.5 to 0.6]), primary care (3.2 [3.0 to 3.4] vs 2.2 [2.1 to 2.3]), medical/surgical subspecialists (2.1 [1.9 to 2.3] vs 1.5 [1.4 to 1.6]), ancillary services (4.1 [3.7 to 4.5] vs 2.4 [2.2 to 2.6]), and diagnostic tests (5.6 [5.1 to 6.1] vs 3.7 [3.4 to 4.0]). In multivariate models adjusted for demographics, smoking, service access, and medical comorbidities, PTSD+ women had greater likelihood of medical/surgical hospitalization (OR=1.37 [1.04 to 1.79]) and of being among the top quartile of patients for visits to the ED, primary care, ancillary services, and diagnostic testing.Female veterans who screen PTSD+ receive more VA medical/surgical services. Appropriateness of that care deserves further study.

Brief primary care interventions for alcohol use should be tailored to patients' readiness to change; however, validated measures of readiness to change are too lengthy to be practical in most primary care settings. We compared a readiness to change drinking algorithm (RTC Algorithm) based on three standardized questions to a validated 12-item readiness to change questionnaire (Rollnick RTCQ) in 85 hazardous drinking female Veterans Affairs (VA) patients. Results from comparisons of mean Rollnick RTCQ scale scores across RTC Algorithm categories suggest good concurrent validity. Regular assessment using the RTC Algorithm questions may help primary care providers tailor alcohol-related discussions with hazardous drinking patients.

This study of women Veterans Affairs (VA) health care patients screened for the prevalence of past-year smoking, hazardous and problem drinking, other drug abuse, and psychiatric disorders.A survey was mailed to women veterans who had received care from VA Puget Sound Health Care System between October 1, 1996, and January 1, 1998. Screening measures included questions about cigarettes; questions from the Alcohol Use Disorders Identification Test about consumption (hazardous drinking); the TWEAK test (problem drinking); a drug abuse screen; the Patient Health Questionnaire (psychiatric conditions); and the PTSD (posttraumatic stress disorder) Checklist.Of eligible patients, 1,257 (65 percent) returned surveys with complete substance use data. Patients reported a relatively high rate of past-year smoking (29.1 percent) and hazardous drinking, problem drinking, or both (31.1 percent). The rate of past-year drug use was much lower (4.9 percent). Younger age was strongly associated with greater substance abuse: 59 percent of women under age 35 screened positive for smoking, hazardous or problem drinking, or drug abuse. Screening positive for a psychiatric condition (N=504) was also associated with substance abuse: The rate of past-year drug abuse among women screening positive for a psychiatric condition (9.7 percent) was double the rate for the entire sample. Of the women who screened positive for depression, PTSD, eating disorders, or panic disorders, 57 percent screened positive for substance abuse (including smoking).Substance abuse is common among women VA patients and is associated with younger age and with screening positive for other psychiatric conditions. Providers are expected to follow up on positive screening tests, and these data indicate substantial provider burden.

We evaluated the screening validity of a self-report measure for post traumatic stress disorder (PTSD), the PTSD Checklist (PCL), in female Veterans Affairs (VA) patients. All women seen for care at the VA Puget Sound Health Care system from October 1996-January 1999 (n=2,545) were invited to participate in a research interview. Participants (n=282) completed the 17-item PCL, followed by a gold standard diagnostic interview for PTSD, the Clinician Administered PTSD Scale (CAPS). Thirty-six percent of the participants (n=100) met CAPS diagnostic criteria for current PTSD. Receiver Operating Characteristic (ROC) analysis was used to evaluate the screening performance of the PCL. The area under the ROC curve was 0.86 (95% CI 0.82-0.90). A PCL score of 38 optimized the performance of the PCL as a screening test (sensitivity 0.79, specificity 0.79). The PCL performed well as a screening measure for the detection of PTSD in female VA patients.

Although Post-traumatic Stress Disorder (PTSD) is common among patients seeking care at medical clinics, little is known about the performance of screening instruments for this disorder in these settings. Previous studies of acute trauma populations using the PTSD Checklist (PCL) have suggested that scores of 45-50 provide the best discrimination between cases and noncases. We gave the PCL to 1,225 randomly selected women enrolled in an HMO. After interviewing a sample of 261 of these women using a structured, clinician-administered PTSD interview, we compared the results of the PCL to the clinician interviews over a range of possible cut scores using Receiver Operating Characteristic analysis. The optimum balance of sensitivity and specificity for this population was a score of 30, yielding a sensitivity of.82 and specificity of.76. The positive and negative likelihood ratios for this cut score were 3.40 and 0.24, respectively. By comparison, the use of 45 as a cut score would result in very low sensitivity (.36) in this setting. The lower cut score found in this study may indicate that the use of previously published cut scores of 45-50 may not optimize the function of the PCL as a screening tool outside of acute trauma settings due to an unacceptably high number of false negative cases.

BACKGROUND Preclinical and clinical observations suggest that the centrally active alpha1-adrenergic antagonist prazosin might alleviate trauma content nightmares and other symptoms in combat veterans with chronic posttraumatic stress disorder (PTSD). METHOD In this retrospective chart review study, we analyzed data from 59 consecutive combat veterans with previously treatment-resistant chronic PTSD (DSM-IV criteria) and severe intractable trauma content nightmares to whom prazosin had been prescribed. Nightmare severity was quantified using the recurrent distressing dreams item of the Clinician Administered PTSD Scale (CAPS). Change in overall PTSD severity exclusive of nightmares was estimated by assigning a Clinical Global Impressions-Change scale (CGI-C) score based on chart review. RESULTS Mean +/- SEM recurrent distressing dreams item scores improved significantly (7.0 +/- 0.2 to 3.5 +/- 0.3, p

© 2014. Background: Neurocognitive deficits in schizophrenia (SZ) are established and the Consortium on the Genetics of Schizophrenia (COGS) investigated such measures as endophenotypes in family-based (COGS-1) and case-control (COGS-2) studies. By requiring family participation, family-based sampling may result in samples that vary demographically and perform better on neurocognitive measures. Methods: The Penn computerized neurocognitive battery (CNB) evaluates accuracy and speed of performance for several domains and was administered across sites in COGS-1 and COGS-2. Most tests were included in both studies. COGS-1 included 328 patients with SZ and 497 healthy comparison subjects (HCS) and COGS-2 included 1195 patients and 1009 HCS. Results: Demographically, COGS-1 participants were younger, more educated, with more educated parents and higher estimated IQ compared to COGS-2 participants. After controlling for demographics, the two samples produced very similar performance profiles compared to their respective controls. As expected, performance was better and with smaller effect sizes compared to controls in COGS-1 relative to COGS-2. Better performance was most pronounced for spatial processing while emotion identification had large effect sizes for both accuracy and speed in both samples. Performance was positively correlated with functioning and negatively with negative and positive symptoms in both samples, but correlations were attenuated in COGS-2, especially with positive symptoms. Conclusions: Patients ascertained through family-based design have more favorable demographics and better performance on some neurocognitive domains. Thus, studies that use case-control ascertainment may tap into populations with more severe forms of illness that are exposed to less favorable factors compared to those ascertained with family-based designs.

The children of older fathers have increased risks of developing schizophrenia spectrum disorders, and among those who develop these disorders, those with older fathers present with more severe clinical symptoms. However, the influence of advanced paternal age on other important domains related to schizophrenia, such as quantitative endophenotype deficit levels, remains unknown. This study investigated the associations between paternal age and level of endophenotypic impairment in a well-characterized family-based sample from the Consortium on the Genetics of Schizophrenia (COGS). All families included at least one affected subject and one unaffected sibling. Subjects met criteria for schizophrenia (probands; n = 293) or were unaffected first-degree siblings of those probands (n = 382). Paternal age at the time of subjects’ birth was documented. Subjects completed a comprehensive clinical assessment and a battery of tests that measured 16 endophenotypes. After controlling for covariates, potential paternal age–endophenotype associations were analyzed using one model that included probands alone and a second model that included both probands and unaffected siblings. Endophenotype deficits in the Identical Pairs version of the 4-digit Continuous Performance Test and in the Penn Computerized Neurocognitive Battery verbal memory test showed significant associations with paternal age. However, after correcting for multiple comparisons, no endophenotype was significantly associated with paternal age. These findings suggest that factors other than advanced paternal age at birth may account for endophenotypic deficit levels in schizophrenia.

Clinical studies suggest involvement of brain noradrenergic systems in the pathophysiology of disruptive agitation in Alzheimer’s disease (AD). This behavioral problem is even more prevalent in dementia with Lewy bodies (DLB). Here we used receptor autoradiography with [ 125 I]para-iodoclonidine to estimate alpha-2 adrenergic receptor (A2R) density in locus coeruleus (LC) projection areas in postmortem brain tissue from age and gender comparable groups of DLB (n 5 6), AD (n 5 5) and normal (n 5 7) subjects. LC neuronal loss was substantial and equivalent in DLB and AD. A2R density was greater in DLB than in normals in the deep layers of the frontal cortex. A2R density was greater in DLB than in AD in hippocampus (CA-1, CA-3 and dentate hilus) and in the granule layer of the cerebellum. Increased A2R binding in DLB is consistent with expression of presynaptic A2R on fibers from surviving LC neurons involved in reinnervation of LC projection areas. These areas develop compensatory noradrenergic hyperinnervation in a rat model of partial LC ablation. It is also consistent with upregulation of post-synaptic A2R in response to loss of LC noradrenergic innervation. Either mechanism could lower the threshold for increased agitation in response to noradrenergic outflow in these dementing disorders. © 2001 Elsevier Science Inc. All rights reserved.

Stimulation of brain cholinergic systems increases activity of both the sympathoneural (SN) and sympathoadrenomedullary (SAM) components of the peripheral sympathetic nervous system. Because presynaptic cholinergic neuron numbers are substantially reduced in Alzheimer's disease (AD), we predicted decreased responsiveness in AD of plasma norepinephrine (NE), an estimate of SN activity, and of epinephrine (EPI), an estimate of SAM activity, to central cholinergic stimulation by the cholinesterase inhibitor physostigmine (0.0125 mg/kg i.v.). Because previous studies have demonstrated that normal human aging increases SN activity but not SAM activity, we specifically hypothesized: (1) a smaller NE response to physostigmine in subjects with mild to moderate AD (n=11; age 72+/-2 yrs; mini-mental state exam [MMSE] scores of 19+/-2) than in healthy older subjects (n=20; age 71+/-1 yrs); and (2) a smaller EPI response in AD subjects than in either healthy older or healthy young subjects (n=9; age 27+/-2 yrs). Unexpectedly, the plasma NE increase following physostigmine only achieved significance in AD subjects and plasma EPI responses were greater in both AD and older subjects than in young subjects. Blood pressure responses to physostigmine were consistent with the catecholamine responses. These data suggest that the presence of mild to moderate AD increases the SN response to cholinergic stimulation and that both AD and normal aging increase the SAM response to cholinergic stimulation. As a result, plasma catecholamine responses to physostigmine do not appear to be useful peripheral neuroendocrine estimates of the severity of brain cholinergic deficits in mild to moderate AD.

Background Central nervous system (CNS) adrenergic hyperresponsiveness may be involved in the pathophysiology of posttraumatic stress disorder (PTSD). Two Vietnam combat veterans with PTSD prescribed the centrally active alpha1-adrenergic antagonist prazosin for symptoms of benign prostatic hypertrophy unexpectedly reported elimination of combat trauma nightmares. This observation prompted an open-label feasibility trial of prazosin for combat trauma nightmares in chronic combat-induced PTSD. Method Four consecutively identified combat veterans with chronic DSM-IV PTSD and severe intractable combat trauma nightmares participated in an 8-week open trial of escalating-dose prazosin. Nightmare severity response was rated using the nightmare item of the Clinician Administered PTSD Scale and the Clinical Global Impressions-Change scale. Results The 2 patients who achieved a daily prazosin dose of at least 5 mg were markedly improved, with complete elimination of trauma nightmares and resumption of normal dreaming. The 2 subjects limited to 2 mg of prazosin to avoid excessive blood pressure reduction were moderately improved with at least 50% reduction in nightmare severity. Conclusion These clinical observations, together with neurobiological evidence for alpha1-adrenergic regulation of CNS neurobiological systems relevant to PTSD, provide rationale for placebo-controlled trials of prazosin for PTSD combat trauma nightmares.

Central nervous system (CNS) adrenergic systems are involved in regulation of behavior and blood pressure. The effects of Alzheimer's disease (AD) and normal aging on resting CNS adrenergic activity were estimated by measuring cerebrospinal fluid (CSF) epinephrine (EPI) concentrations in 74 persons with AD, 42 cognitively normal healthy older persons, and 54 healthy young persons. The responsiveness of CSF EPI to the alpha-2 adrenergic antagonist yohimbine and the alpha-2 adrenergic agonist clonidine was measured in smaller subject groups. Resting CSF EPI was higher in AD than in older or young subjects, and increased with dementia severity in AD subjects. There was no relationship between resting CSF EPI and blood pressure. CSF EPI increased following yohimbine in AD and older subjects but not in young subjects. CSF EPI was unaffected by clonidine in all subject groups. The agitation increase following yohimbine was substantially greater in AD subjects than in older or young subjects. CNS adrenergic activity seems increased in AD, may further increase as AD progresses, and may be involved in the pathophysiology of agitation.

Haloperidol is believed to induce neurotensin/neuromedin N (NT/ N) gene expression in the dorsolateral striatum (DLST) of the rat brain via dopamine D2 receptor blockade, but is also known to interact with other receptors as well. To further characterize haloperidol's effects, rats were treated with the irreversible monoaminergic receptor antagonist N-ethoxycarbonyl-2-ethoxy-1,2 hydroxyquinolone (EEDQ). In situ hybridization was performed for NT/N mRNA. D2-like and sigma receptor autoradiography was performed using 125I-sulpride and 3H-1,3-di-o-tolylguanidine (DTG), respectively. Despite antagonism of D2 receptors, pretreatment with EEDQ failed to significantly reduce the NT/N mRNA response when given 3 days prior to the haloperidol challenge. These data suggest that the acute effects of haloperidol on NT/N mRNA expression in large part result from D2 receptor antagonism. Nonetheless, a contribution of other receptors can not be excluded.

To assess the effects of aging on hypothalamic-pituitary-adrenal (HPA) axis responsivity, we compared the plasma cortisol and adrenocorticotropin (ACTH) responses to hypertonic saline infusion between normal older and young human volunteers. We administered a 90 min hypertonic saline infusion (5% sodium chloride at 0.06 ml/kg/min) and a 90 min placebo infusion (0.9% sodium chloride at 0.06 ml/kg/min) to normal young subjects (n = 13, age = 29 +/- 2 years) and normal older subjects (n = 8, age = 63 +/- 3 years). Plasma cortisol, ACTH, osmolality and arginine vasopressin (AVP) were measured before and at 30 min intervals during the infusions. The rate of increase in plasma osmolality and AVP induced by hypertonic saline infusion was similar between groups. The plasma cortisol increase during hypertonic saline infusion was greater in normal older subjects than in young subjects (p = .03), but a stimulatory effect of hypertonic saline infusion on plasma ACTH was not apparent in either older or young subjects. These results suggest increased sensitivity with human aging to stimulation of cortisol release by hypertonic saline infusion at the adrenocortical level of the HPA axis.

Neuroleptic drugs such as haloperidol (H) induce a rapid increase in neurotensin/neuromedin N (NT/N) gene expression in the dorsolateral striatum (DLSt) and nucleus accumbens (NA) in young adult rats. This effect may be mediated by post-receptor effectors that are activated by dopamine D2 receptor antagonism. The regional pattern of induction of neurotensin gene expression correlates with the side effect profile of particular neuroleptics. As motor side effects of H differ in aged animals, we hypothesized that the regional expression of the neurotensin gene may differ between young and old animals. We administered H or saline acutely to 3, 14, and 25 month-old Fischer 344 rats, followed by in situ hybridization and quantitative autradiography for NT/N mRNA. There was a significant age effect on the H-induced NT/N mRNA response in the DLSt, but not the NA, of older animals. In addition to the blunted NT/N mRNA response, significant decreases in D2 receptor mRNA were observed in the lateral striatum of another group of young, middle-aged, and aged rats. Age-related blunting of the NT/N mRNA response to H in the DLSt may be due in part to a decrease in D2 receptors in this structure.

Inhibition of the P50 evoked electroencephalographic response to the second of paired auditory stimuli has been frequently examined as a neurophysiological deficit in schizophrenia. The National Institute of Mental Health Consortium on the Genetics of Schizophrenia (COGS) examined this endophenotype in a 7 center multi-site study. Recordings were analyzed from 181 probands with schizophrenia, 429 of their first degree relatives, and 333 community comparison control subjects. Most probands were being treated with second generation neuroleptic medications. Highly significant differences in P50 inhibition, measured as either the ratio of amplitudes or their difference in response to the two stimuli, were found between the probands and the community comparison sample. There were no differences between the COGS sites for these findings. For the ratio parameter, an admixture analysis indicated that nearly 40% of the relatives demonstrated deficiencies in P50 inhibition that are comparable to the deficit found in the probands. These results indicate that P50 auditory evoked potentials can be recorded across multiple sites and reliably demonstrate a physiological abnormality in schizophrenia. The appearance of the physiological abnormality in a substantial proportion of clinically unaffected first degree relatives is consistent with the hypothesis that deficits in cerebral inhibition may be a familial neurobiological risk factor for the illness.

The antisaccade task is a widely used technique to measure failure of inhibition, an important cause of cognitive and clinical abnormalities found in schizophrenia. Although antisaccade performance, which reflects the ability to inhibit prepotent responses, is a putative schizophrenia endophenotype, researchers have not consistently reported the expected differences between first-degree relatives and comparison groups. Schizophrenia participants (n=219) from the large Consortium on the Genetics of Schizophrenia (COGS) sample (n=1078) demonstrated significant deficits on an overlap version of the antisaccade task compared to their first-degree relatives (n=443) and community comparison subjects (CCS; n=416). Although mean antisaccade performance of first-degree relatives was intermediate between schizophrenia participants and CCS, a linear mixed-effects model adjusting for group, site, age, and gender found no significant performance differences between the first-degree relatives and CCS. However, admixture analyses showed that two components best explained the distributions in all three groups, suggesting two distinct doses of an etiological factor. Given the significant heritability of antisaccade performance, the effects of a genetic polymorphism is one possible explanation of our results.

The biosynthetic activity of extra-hypothalamic vasopressin (VP) neurons in the bed nucleus of the stria terminalis (BNST) is regulated by gonadal steroids. These neurons have also been implicated in a number of behaviors that are impaired in aging. We previously reported that VP mRNA labelling in the BNST is decreased in senescent rats. We hypothesized that the age-related decrease in VP mRNA labelling is due to the decline in circulating testosterone (T) levels in aged animals. T or saline was administered peripherally for 1 month in physiologic or superphysiologic doses to 3 month old or 24 month old Fischer 344 male rats. In situ hybridization and quantitative autoradiography for VP mRNA in the BNST were performed using a 48-base 35S-labelled oligonucleotide probe. Administration of T completely reversed the decline in VP mRNA labelling in the aged animals. Superphysiologic T further increased VP gene expression in both age groups. These data are consistent with a previous report of T-induced increase in VP immunoreactive fiber density in other extrahypothalamic regions of the brain in aged rats. This study offers further evidence that alterations in the hormonal milieu may play an important role in modulating neuronal biosynthetic activity in senescence.

To determine whether aging influences arginine vasopressin (AVP) biosynthesis in the extrahypothalamic neurons of the bed nucleus of the stria terminalis (BNST), we used in situ hybridization and quantitative autoradiography to compare AVP mRNA in 3-month-old, 14-month-old, and 24-month-old male Fischer 344 rats. As AVP synthesis in the BNST has previously been shown to be steroid-dependent, plasma testosterone (T) was measured by radioimmunoassay. The 24-month-old animals had significantly fewer AVP-labelled cells than either the 3-month-old (p less than 0.01) or 14-month-old (p less than 0.05) animals. The cells that were present in the 24-month animals were less intensely labelled than in the other groups, as indicated by a significantly reduced number of grains per cell (p less than 0.01). Plasma T was also significantly lower in 24-month-old animals when compared with 3-month (p less than 0.01) or 14-month (p less than 0.05) groups. The results indicate that there is a marked age-related decline in vasopressin biosynthetic activity in neurons of the BNST.

Background N100 evoked potential amplitude and gating abnormalities have been widely observed in schizophrenia patients. However, previous studies have been inconclusive as to whether similar deficits are present in unaffected family members. The Consortium on the Genetics of Schizophrenia (COGS) is a multisite National Institute of Mental Health (NIMH) initiative examining neurocognitive and neurophysiological measures as endophenotypes for genetic studies of schizophrenia. We report initial results from the COGS dataset of auditory N100 amplitude and gating as candidate endophenotypes. Methods Evoked potential data were acquired from 142 schizophrenia probands, 373 unaffected first-degree relatives, and 221 community comparison subjects (CCS), using an auditory paired-click stimulation paradigm. Amplitude of the N100 response to each click and the click 2/click 1 ratio were dependent variables. Heritability was estimated based on kinships using Solar v.2.1.2. Group differences were examined after subjects were categorized as either "broad" or "narrow," based on the presence (broad) or absence (narrow) of nonpsychotic psychiatric comorbidity. Results Heritability estimates were .40 and .29 for click1 and click2 amplitudes and .22 for the ratio. Broad and narrow patients both had impaired click 1 amplitudes. Broad relatives, but not narrow relatives, exhibited similar impairments. There were no group differences for either click 2 amplitude or the gating ratio. Conclusions N100 amplitude is a heritable measure that is abnormal in patients and a subset of relatives for whom psychiatric comorbidity may be a genetically associated phenotype. Auditory N100 gating, although heritable, is less viable as a schizophrenia endophenotype.

This study reports on the feasibility of using validated mental health screening instruments for deployed Operation Iraqi Freedom military personnel.For a 3-month period in 2005, all service members (N=296) who initially presented to the U.S. Military Hospital Kuwait mental health clinic completed an intake questionnaire that gathered demographic information and contained validated instruments to screen for mental disorders and functional impairment.A total of 19% of the sample subjects screened positive for post-traumatic stress disorder-related symptoms, 35% for a major depressive disorder, and 11% for severe misuse of alcohol. Significant levels of distress and functional impairment were reported by 58% of the sample. Women represented a disproportionately high percentage of those presenting for care (27%).Screening instruments were well accepted and useful in detecting psychopathological conditions and functional impairment. Female service members might represent a high-risk group. These results are useful for those caring for service members during or after deployment.

Background Startle and its inhibition by weak lead stimuli (“prepulse inhibition”: PPI) are studied to understand the neurobiology of information processing in patients and community comparison subjects (CCS). PPI has a strong genetic basis in infrahumans, and there is evidence for its heritability, stability and reliability in humans. PPI has gained increasing use as an endophenotype to identify vulnerability genes for brain disorders, including schizophrenia. Genetic studies now often employ multiple, geographically dispersed test sites to accommodate the need for large and complex study samples. Here, we assessed the feasibility of using PPI in multi-site studies. Methods Within a 7-site investigation with multiple measures, the Consortium on the Genetics of Schizophrenia conducted a methodological study of acoustic startle and PPI in CCS. Methods were manualized, videotaped and standardized across sites with intensive in-person training sessions. Equipment was acquired and programmed at the “PPI site” (UCSD), and stringent quality assurance (QA) procedures were used. Testing was completed on 196 CCS over 2.5 years, with 5 primary startle dependent measures: eyeblink startle magnitude, habituation, peak latency, latency facilitation and PPI. Results Analyses identified significant variability across sites in some but not all primary measures, and determined factors both within the testing process and subject characteristics that influenced a number of test measures. QA procedures also identified non-standardized practices with respect to testing methods and procedural “drift”, which may be particularly relevant to multi-site studies using these measures. Conclusion With thorough oversight and QA procedures, measures of acoustic startle PPI can be acquired reliably across multiple testing sites. Nonetheless, even among sites with substantial expertise in utilizing psychophysiological measures, multi-site studies using startle and PPI as dependent measures require careful attention to methodological procedures.

The antisaccade task is a promising schizophrenia endophenotype; it is stable over time and reflects neurophysiological deficits present in both schizophrenia subjects and their first-degree relatives. Meaningful genetic research requires large sample sizes that are best ascertained using multi-site study designs. To establish the criterion validity of the antisaccade task in a multi-site design, the Consortium on the Genetics of Schizophrenia (COGS) examined whether seven sites could detect previously reported antisaccade deficits in schizophrenia subjects. Investigators presented 3 blocks of 20 antisaccade stimuli to 143 schizophrenia subjects and 195 comparison subjects. Frequent collaborator communication, standardized training, and ongoing quality assurance optimized testing uniformity. Data were discarded from only 1.2% of subjects due to poor quality, reflecting the high fidelity of data collection and scoring methods. All sites detected a significant difference in the proportion of correct antisaccades between schizophrenia and comparison subjects (p

To determine the prevalence and frequency of mastalgia and its association with psychiatric conditions and unexplained pain syndromes.Cross-sectional mailed survey completed by 1,219 female veterans enrolled at the VA Puget Sound Health Care System in 1998.Breast pain in the past year, unrelated to pregnancy, was categorized as infrequent (or =monthly) or frequent (or =weekly) mastalgia. Surveys assessed posttraumatic stress disorder (PTSD), depression, panic disorder, and alcohol misuse with validated screening tests, as well as self-reported past-year chronic pelvic pain, fibromyalgia, and irritable bowel syndrome.The response rate was 63%. Fifty-five percent of the respondents reported past-year mastalgia. Of these, 15% reported frequent mastalgia. Compared to women without mastalgia, women reporting frequent mastalgia were more likely to screen positive for PTSD (odds ratio [OR] 5.2, 95% confidence interval [CI] 3.2 to 8.4), major depression (OR 4.2, 2.6 to 6.9), panic disorder (OR 7.1, 3.9 to 12.8), eating disorder (OR 2.6, 1.5 to 4.7), alcohol misuse (OR 1.8, 1.1 to 2.8), or domestic violence (OR 3.1, 1.9 to 5.0), and to report fibromyalgia (OR 3.9, 2.1 to 7.4), chronic pelvic pain (OR 5.4, 2.7 to 10.5), or irritable bowel syndrome (OR 2.8, 1.6 to 4.8). Women with infrequent mastalgia were also more likely than women without mastalgia to screen positive for PTSD, depression, or panic disorder, or report pelvic pain or irritable bowel syndrome, although associations were weaker than with frequent mastalgia.Like other unexplained pain syndromes, frequent mastalgia is strongly associated with PTSD and other psychiatric conditions. Clinicians seeing patients with frequent mastalgia should inquire about anxiety, depression, alcohol misuse, and trauma history.

To estimate the prevalence of hysterectomy and associated factors in women veterans who access care at a Veterans Affairs medical center.A survey that included questions regarding hysterectomy status, demographics, medical history and validated mental health measures was mailed to 1,935 women who received care at the VA Puget Sound Health Care System between October 1996 and January 1998.The overall prevalence of hysterectomy was 32%, with 12% of 18-39-year-olds, 35% of 40-49-year-olds, and 57% of women 50 years old or older reporting having had a hysterectomy. In multivariable analyses, older age (OR 1.1, 95% CI 1.07-1.09), multiparity (OR 1.6, 1.14-2.2), self-reported polycystic ovary syndrome (OR 3.3, 1.81-5.9), chronic pelvic pain (OR 3.2, 2.1-4.9), irritable bowel syndrome (OR 1.8, 1.3-3.1) and premenstrual syndrome (OR 1.6, 1.1-2.3) were associated with prior hysterectomy. When factors associated with posttraumatic stress disorder in this population were omitted from the model, age (OR 1.07, 1.05-1.08), multiparity (OR 1.4, 1.0-1.9), a family history of ovarian cancer (OR 1.8, 1.2-2.8) and posttraumatic stress disorder (OR 1.4, 1.02-1.87) were associated with prior hysterectomy.The prevalence of hysterectomy may be higher among women veterans as compared with published rates for the general population and may be related to chronic pain syndromes and/or posttraumatic stress disorder.

Background: The optimal brief questionnaire for alcohol screening among female patients has not yet been identified. This study compared the performance of the TWEAK (tolerance, worried, eye-opener, amnesia, cutdown), the Alcohol Use Disorders Identification Test (AUDIT), and the AUDIT Consumption (AUDIT-C) as self-administered screening tests for hazardous drinking and/or active alcohol abuse or dependence among female Veterans Affairs (VA) outpatients. Methods: Women were included in the study if they received care at VA Puget Sound and completed both a self-administered survey containing the AUDIT and TWEAK screening questionnaires and subsequent in-person interviews with the Alcohol Use Disorders and Associated Disabilities Interview Schedule. Sensitivities, specificities, positive and negative likelihood ratios, and areas under Receiver Operating Characteristic curves were computed for each screening questionnaire compared with two interview-based comparison standards: (1) active DSM-IV alcohol abuse or dependence and (2) hazardous drinking and/or active DSM-IV alcohol abuse or dependence, the more appropriate target for primary care screening. Results: Of 393 women who completed screening questionnaires and interviews, 39 (9.9%) met diagnostic criteria for alcohol abuse or dependence, and 89 (22.7%) met criteria for hazardous drinking or alcohol abuse or dependence. The TWEAK had relatively low sensitivities (0.62 and 0.44) but adequate specificities (0.86 and 0.89) for both interview-based comparison standards, even at its lowest cut-point (≥1). The AUDIT and AUDIT-C were superior, with the following areas under the receiver operating characteristic curve for active alcohol abuse or dependence and hazardous drinking and/or active alcohol abuse or dependence, respectively: AUDIT, 0.90 [95% confidence interval (CI), 0.85–0.95] and 0.87 (95% CI, 0.84–0.91); AUDIT-C, 0.91 (95% CI, 0.88–0.95) and 0.91 (95% CI, 0.88–0.94); and TWEAK, 0.76 (95% CI, 0.66–0.86) and 0.67 (95% CI, 0.60–0.74). Conclusions: The TWEAK has low sensitivity as an alcohol-screening questionnaire among female VA outpatients and should be evaluated further before being used in other female primary care populations. The three-item AUDIT-C was the optimal brief alcohol-screening questionnaire in this study.

Background Primary care physicians need a brief alcohol questionnaire that identifies hazardous drinking and alcohol use disorders. The Alcohol Use Disorders Identification Test (AUDIT) questions 1 through 3 (AUDIT-C), and AUDIT question 3 alone are effective alcohol-screening tests in male Veterans Affairs (VA) patients, but have not been validated in women. Methods Female VA patients (n = 393) completed self-administered questionnaires, including the 10-item AUDIT and a previously proposed modification to AUDIT question 3 with a sex-specific threshold for binge drinking (≥4 drinks/occasion), and in-person interviews with the Alcohol Use Disorder and Associated Disabilities Interview Schedule. The AUDIT-C, AUDIT question 3 alone, and the 10-item AUDIT were each evaluated with and without the sex-specific binge question and compared with past-year hazardous drinking (>7 drinks/week or ≥4 drinks/occasion) and/or active Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition alcohol abuse or dependence, based on interviews. Results Eighty-nine women (22.6%) met interview criteria for past-year hazardous drinking and/or active alcohol abuse or dependence. Standard and sex-specific AUDIT-Cs were sensitive (0.81 and 0.84, respectively) and specific (0.86 and 0.85, respectively). Their areas under the receiver operating characteristic curves were equivalent (0.91, and 0.92, respectively) and slightly higher than for the standard 10-item AUDIT (0.87). A single, sex-specific question about binge drinking (modified AUDIT question 3) had a sensitivity of 0.69 and specificity of 0.94, whereas the standard AUDIT question 3 was specific (0.96) but relatively insensitive (0.45). Conclusions The standard and sex-specific AUDIT-Cs are effective screening tests for past-year hazardous drinking and/or active alcohol abuse or dependence in female patients in a VA study.

Prazosin is a centrally active alpha(1) adrenergic antagonist. The authors' goal was to evaluate prazosin efficacy for nightmares, sleep disturbance, and overall posttraumatic stress disorder (PTSD) in combat veterans.Ten Vietnam combat veterans with chronic PTSD and severe trauma-related nightmares each received prazosin and placebo in a 20-week double-blind crossover protocol.Prazosin (mean dose=9.5 mg/day at bedtime, SD=0.5) was superior to placebo for the three primary outcome measures: scores on the 1) recurrent distressing dreams item and the 2) difficulty falling/staying asleep item of the Clinician-Administered PTSD Scale and 3) change in overall PTSD severity and functional status according to the Clinical Global Impression of change. Total score and symptom cluster scores for reexperiencing, avoidance/numbing, and hyperarousal on the Clinician-Administered PTSD Scale also were significantly more improved in the prazosin condition, and prazosin was well tolerated.These data support the efficacy of prazosin for nightmares, sleep disturbance, and other PTSD symptoms.

Background: Decreased basal cortisol levels have been reported in individuals with posttraumatic stress disorder (PTSD). There is evidence for enhanced negative feedback sensitivity of the hypothalamic-pituitary-adrenal (HPA) axis in PTSD, which could account for this, but other possible mechanisms have not been ruled out. We examined the HPA axis employing a metyrapone-cortisol infusion protocol designed to study negative feedback sensitivity. Methods: Vietnam combat trauma-exposed subjects met DSM-IV criteria for PTSD. Exclusion criteria included substance abuse and most medications. Endogenous feedback inhibition was removed by blocking cortisol synthesis with oral metyrapone and reintroduced by intravenous infusion of cortisol. In a placebo condition, subjects received oral placebo and normal saline infusion. Serial blood samples drawn over 4 hours were assayed for adrenocorticotrophic hormone (ACTH), cortisol, and 11-deoxycortisol. Selected samples were assayed for cortisol binding globulin (CBG) and dehydroepiandrosterone (DHEA). Results: Basal plasma cortisol was significantly decreased in PTSD subjects ( n = 13) compared with control subjects ( n = 16). No significant difference in the ACTH response to cortisol infusion following metyrapone was observed; however 11-deoxycortisol was significantly decreased in PTSD subjects. In addition, CBG was significantly increased in PTSD subjects, and DHEA was significantly decreased in both PTSD and combat-exposed control subjects. Conclusions: These observations suggest decreased adrenocortical responsiveness may be an additional or alternative mechanism accounting for low cortisol in PTSD.

Background. The effects of aging on sympathetic nervous system and adrenomedullary outflow were estimated by the measurement of plasma norepinephrine (NE) and epinephrine (EPI) responses to yohimbine and clonidine in healthy young and healthy older subjects. Methods. Yohimbine (0.65 mg/kg), clonidine (5 m g/kg), and placebo were administered on separate days in random order to 5 healthy older men (age 74 6 1 years) and 18 healthy young men (age 26 6 1 years). NE and EPI were measured by radioenzymatic assay in plasma samples obtained before and 30, 60, and 90 minutes after drug administration. Results. Plasma NE increases after yohimbine were greater in older men than in young men, but plasma NE decreases following clonidine did not differ between groups. Plasma NE and systolic blood pressure were higher in older men than in young men at baseline but no longer differed 90 minutes after clonidine. Plasma EPI increases after yohimbine and decreases after clonidine did not differ between groups. Conclusions. These results suggest increased sympathetic nervous system outflow in human aging that is not a function of reduced responsiveness of alpha-2 adrenoreceptor-mediated feedback inhibition.

We asked whether hypothalamic-pituitary-adrenocortical (HPA) axis responses to a cholinergic stimulus are blunted in patients with Alzheimer's disease (AD) of mild to moderate severity. Such a finding would be consistent with a central cholinergic deficiency early in the course of AD. To address this question, we measured the plasma adrenocorticotropic hormone (ACTH), beta-endorphin-like immunoreactivity (beta E-LI), and cortisol responses to the cholinesterase inhibitor physostigmine in 10 healthy normal older subjects (age = 71 +/- 2 years) and 11 outpatients with probable AD (age = 72 +/- 2 years; Mini Mental State Exam score = 19 +/- 2). Cortisol concentrations were higher in AD subjects throughout the study, but AD and normal older subjects had similar robust ACTH, beta E-LI, and cortisol responses to physostigmine. In all subjects combined, women had greater ACTH, beta E-LI, and cortisol responses to physostigmine than did men. Plasma physostigmine concentrations did not differ between groups. These results suggest that female gender enhances the magnitude of HPA axis responses to cholinergic stimulation in older humans; however, the HPA axis response to physostigmine does not appear to reflect central cholinergic deficiency in the early stages of AD.

Background: The resting cerebrospinal fluid (CSF) norepinephrine concentration is unchanged or even increased in patients with Alzheimer's disease (AD). These in vivo findings appear to be inconsistent with the postmortem locus ceruleus neuronal loss that is reported in patients with AD. Methods: The effects of AD and advanced age on central nervous system noradrenergic status were estimated by comparing CSF norepinephrine concentrations following the administration of yohimbine hydrochloride, clonidine hydrochloride, and placebo in outpatients with AD and older and young normal subjects. Levels of yohimbine, its metabolite 11-hydroxy-yohimbine, and clonidine were measured in CSF and plasma samples. Behavioral responses were quantified by rating the Tension, Excitement, and Anxiety items on the Brief Psychiatric Rating Scale. Results: Yohimbine-induced increases of CSF norepinephrine concentrations were greater in both patients with AD and normal older subjects than in normal young subjects. Clonidine-induced decreases of CSF norepinephrine concentrations did not differ among groups. Behavioral arousal following the administration of yohimbine was greater in patients with AD than in the other groups. Conclusions: Central nervous system noradrenergic responsiveness is enhanced in normal older subjects, and this age effect is retained in patients with AD. Behavioral sensitivity to increased central nervous system noradrenergic activity is enhanced in patients with AD.

BACKGROUND The purpose of this study was to determine the effects of normal human aging on the hypothalamic-pituitary-adrenocortical (HPA) axis response to the centrally active cholinesterase inhibitor physostigmine. This drug stimulates the HPA axis at a suprapituitary level by increasing central nervous system (CNS) cholinergic activity. METHODS Plasma ACTH, beta-endorphin (beta E) and cortisol responses to a 10-minute infusion of physostigmine (.0125 mg/kg) were compared between groups of 10 normal older subjects (71 +/- 2 years [mean +/- SEM]) and 9 normal young subjects (27 +/- 2 years). Plasma physostigmine concentrations were measured to assess the comparability of the pharmacologic stimulus between groups. RESULTS Endocrine responses were substantially greater in older subjects than young subjects for ACTH (p < .01), beta E (p < .01) and cortisol (p < .01). Plasma physostigmine concentrations did not differ between older and young subjects. CONCLUSION This study demonstrated increased HPA axis responsivity to a CNS cholinergic stimulus in normal human aging.

Effects of aging on the expression of dopamine D2 receptor isoforms (D2-long and -short) in neostriatal subregions was examined by in situ hybridization histochemistry. Hybridization of a probe selective for the D2-long transcript was compared with signal generated by a probe recognizing both variants of D2 mRNA. Lateral quadrants of the neostriatum in old rats appeared to show declines in primarily the long transcripts. On the other hand, decreases in the expression of D2-short transcripts appeared to occur during aging in the ventromedial region of the striatum. These data suggest that the mechanisms involved in alternative splicing of D2 mRNA may be differentially altered in neostriatal subregions during aging.

We recently demonstrated in patients with panic disorder that hypertonic saline infusion induces acute panic with the same frequency and intensity as the standard hypertonic sodium lactate infusion. We now report the effects in normal men of hypertonic saline infusion on neuroendocrine systems possibly relevant to panic and anxiety. We administered a 150-min infusion of hypertonic saline (5% sodium chloride) which increased plasma osmolality from 288 +/- 1 to 303 +/- 2 mOsm/kg and produced the appropriate increase of plasma arginine vasopressin (AVP). Plasma norepinephrine (NE) increased substantially during hypertonic saline infusion compared to a normal saline infusion of equal volume and duration. Mean arterial pressure (MAP) also increased and there were significant positive correlations between MAP and NE, but not between MAP and AVP during hypertonic saline infusion. Plasma epinephrine and cortisol did not differ between conditions. Although the pattern of plasma adrenocorticotrophic hormone (ACTH) response differed between hypertonic saline and normal saline conditions, ACTH concentrations did not increase compared to baseline in either condition. These data suggest that hypertonic saline infusion increases sympathetic nervous system activity in normal men.

In this chapter, we have presented evidence for several potential levels of interaction of NT/N gene products with dopaminergic systems of the brain. We have focused on one manifestation of this interaction related to the effects of antipsychotic drugs on expression of the NT/N gene in two anatomically discrete populations of neurons. It appears that certain antipsychotic drugs can dramatically increase expression of this gene in the dorsolateral striatum by blocking dopamine D2 receptors, perhaps by increasing expression of the gene encoding the transcriptional regulator fos. In addition, a second group of NT cells in the shell region of the nucleus accumbens also respond to these drugs by increasing NT/N gene expression. Several other peptides have been suggested to respond to treatment with antipsychotic drugs. However, there are some important differences with respect to their effects on the NT cells we have studied. The most important of these is the differential responsiveness of the DLSt and nucleus accumbens NT neurons to typical and atypical antipsychotics. We showed that all antipsychotic drugs tested increased NT/N mRNA gene expression in the accumbens, a region thought to be involved in dopaminergic disturbances underlying psychosis. However, only the typical neuroleptics that have a high propensity to induce acute extrapyramidal motor side effects influenced NT/N gene expression in the dorsolateral striatum, a structure importantly involved in regulation of motor functions. We hypothesize, therefore, that NT/N-expressing neuronal systems in the nucleus accumbens may mediate some or all of the antipsychotic effects, whereas those in the dorsolateral striatum may be involved in motor effects of neuroleptic drugs. Thus, examination of the effects of these drugs on these neuronal populations will not only clarify their mechanism of action, but in addition may provide a useful "screening" assay for new drugs with enhanced antipsychotic activity, but reduced propensity to induce the debilitating extrapyramidal side effects that are a major cause of patient noncompliance. Future studies will focus on the effects of antipsychotic drugs on NT neurons in clinically relevant models of chronic administration, and on the molecular events involved in their effects on expression of the NT/N gene in the brain.