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N-glycanase 1 (NGLY1) deficiency is a rare inherited disorder characterized by developmental delay, hypolacrima or alacrima, seizure, intellectual disability, motor deficits, and other neurological symptoms. The underlying mechanisms of the NGLY1 phenotype are poorly understood, and no effective therapy is currently available. Similar to human patients, the rat model of NGLY1 deficiency, Ngly1−/−, shows developmental delay, movement disorder, somatosensory impairment, scoliosis, and learning disability. Here we show that single intracerebroventricular administration of AAV9 expressing human NGLY1 cDNA (AAV9-hNGLY1) to Ngly1−/− rats during the weaning period restored NGLY1 expression in the brain and spinal cord, concomitant with increased enzymatic activity of NGLY1 in the brain. hNGLY1 protein expressed by AAV9 was found predominantly in mature neurons, but not in glial cells, of Ngly1−/− rats. Strikingly, intracerebroventricular administration of AAV9-hNGLY1 normalized the motor phenotypes of Ngly1−/− rats assessed by the rota-rod test and gait analysis. The reversibility of motor deficits in Ngly1−/− rats by central nervous system (CNS)-restricted gene delivery suggests that the CNS is the primary therapeutic target organs for NGLY1 deficiency, and that the Ngly1−/− rat model may be useful for evaluating therapeutic treatments in pre-clinical studies.

Background No data on the long-term ‘real-world’ use of fluvoxamine for the treatment of social anxiety disorder (SAD) in Japanese patients are currently available. Objective To evaluate the long-term safety and efficacy of fluvoxamine for SAD in the clinical setting. Methods Japanese patients with SAD who initiated treatment with fluvoxamine were enrolled in this 53-week post-marketing survey from 407 institutions nationwide. Data including rates of adverse drug reactions (ADRs) and efficacy were collected. Overall improvement was assessed using the Clinical Global Impression for Improvement. SAD symptoms and treatment responses were assessed with the Japanese version of the Liebowitz Social Anxiety Scale. Results From the 1,974 patients surveyed, 1,790 and 1,504 patients were eligible for analysis of safety and efficacy, respectively. ADRs were reported in 18.2 % of patients, with nausea, somnolence, and constipation the most common. Over 50 % of these ADRs developed in the first 4 weeks of treatment. Serious ADRs were reported in 0.8 % of patients and included six cases of suicide attempt and three cases of suicidal ideation. Response to fluvoxamine was reported in 78.4 % of patients. In patients comorbid with depression, improvement in SAD symptoms with fluvoxamine treatment was significantly affected by clinical improvement in the depression. Conclusions These findings support the long-term safety and efficacy of fluvoxamine in patients with SAD. Most ADRs developed during the early treatment phase, and higher doses during the later phase were not associated with an increase in ADRs. Electronic supplementary material The online version of this article (doi:10.1007/s40801-014-0005-2) contains supplementary material, which is available to authorized users.

The psychotomimetic effects of stimulant drugs including amphetamines and cocaine are known to change during the postnatal development in humans and experimental animals. To obtain an insight into the molecular basis of the onset of stimulant-induced psychosis, we have explored the gene transcripts that differentially respond to methamphetamine (MAP) in the developing rat brains using a differential cloning technique, the RNA arbitrarily-primed PCR. We identified from the rat neocortex a novel and developmentally regulated MAP-inducible gene mrt3 (MAP responsive transcript 3) that is transcribed to a presumable non-coding RNA of 3.8kb and is located on the reverse strand of the F-box/LRR-repeat protein 17-like gene mapped on the rat chromosome Xq12. The mrt3 mRNAs are predominantly expressed in the brain and lung. Acute MAP injection upregulated the mrt3 expression in the neocortex at postnatal day 50, but not days 8, 15 and 23, in a D1 receptor antagonist-sensitive manner. This upregulation was mimicked by another stimulant, cocaine, whereas pentobarbital and D1 antagonist failed to alter the mrt3 expression. Moreover, repeated treatment with MAP for 5 days inhibited the ability of the challenge dose of MAP or cocaine to increase the neocortical mrt3 expression without affecting the basal mrt3 mRNA levels on day 14 of withdrawal. These late-developing, cocaine-cross reactive, D1 antagonist-sensitive and long-term regulations of mrt3 by MAP are similar to those of stimulant-induced behavioral sensitization, a model of the onset and relapse of stimulant-induced psychosis and schizophrenia, and therefore may be associated with the pathophysiology of the model.

In an in vivo dialysis experiment, the intra-medial frontal cortex infusion of a system A and Asc-1 transporter inhibitor, S-methyl-L-cysteine, caused a concentration-dependent increase in the dialysate contents of an endogenous coagonist for the N-methyl-D-aspartate (NMDA) type glutamate receptor, D-serine, in the cortical portion. These results suggest that these neutral amino acid transporters could control the extracellular D-serine signaling in the brain and be a target for the development of a novel threapy for neuropsychiatric disorders with an NMDA receptor dysfunction.

In the mammalian brain, kynurenine aminotransferase II (KAT II) and kynurenine 3-monooxygenase (KMO), key enzymes of the kynurenine pathway of tryptophan degradation, form the neuroactive metabolites kynurenic acid (KYNA) and 3-hydroxykynurenine (3-HK), respectively. Although physically segregated, both enzymes use the pivotal kynurenine pathway metabolite L-kynurenine as a substrate. We studied the functional consequences of this cellular compartmentalization in vivo using two specific tools, the KAT II inhibitor BFF 122 and the KMO inhibitor UPF 648. The acute effects of selective KAT II or KMO inhibition were studied using a radiotracing method in which the de novo synthesis of KYNA, and of 3-HK and its downstream metabolite quinolinic acid (QUIN), is monitored following an intrastriatal injection of 3H-kynurenine. In naïve rats, intrastriatal BFF 122 decreased newly formed KYNA by 66%, without influencing 3-HK or QUIN production. Conversely, UPF 648 reduced 3-HK synthesis (by 64%) without affecting KYNA formation. Similar, selective effects of KAT II and KMO inhibition were observed when the inhibitors were applied acutely together with the excitotoxin QUIN, which impairs local KP metabolism. Somewhat different effects of KMO (but not KAT II) inhibition were obtained in rats that had received an intrastriatal QUIN injection 7 days earlier. In these neuron-depleted striata, UPF 648 not only decreased both 3-HK and QUIN production (by 77% and 66%, respectively) but also moderately raised KYNA synthesis (by 27%). These results indicate a remarkable functional segregation of the two pathway branches in the brain, boding well for the development of selective KAT II or KMO inhibitors for cognitive enhancement and neuroprotection, respectively.

This study examined the effects of the selective 5-HT1A receptor agonist osemozotan on repeated methamphetamine (METH)-induced behavioral sensitization and single METH-induced locomotor stimulant effect in mice, and then the neurochemical mechanisms using in vivo microdialysis. Repeated administration of METH for 7 days enhanced METH challenge-induced locomotor activity, and this sensitization was observed even after its withdrawal for 7–14 days. Administration of osemozotan to METH-sensitized mice inhibited the maintenance of behavioral sensitization. This effect was blocked by a low dose of WAY100635, a selective 5-HT1A receptor antagonist. A METH challenge increased the extracellular levels of dopamine (DA), 5-HT, and noradrenaline in the prefrontal cortex, but only the increase in 5-HT release was enhanced by repeated METH administration. This augmented response of 5-HT release was attenuated by osemozotan in a WAY100635-sensitive way. A single administration of osemozotan to drug naive mice inhibited METH-induced locomotor stimulant effect and reduced METH-induced increase in prefrontal 5-HT, but not DA, release. These results suggest that prefrontal 5-HT release is involved at least partly in the effects of osemozotan on single and repeated METH-induced behavioral effects in mice, and imply that the 5-HT1A receptors may have a potential therapeutic value in the remission of schizophrenia.

Spontaneous recurrence of methamphetamine- or amphetamine-induced paranoid hallucinatory psychosis (i.e., flashbacks) occasionally occurs in response to non-specific mild stress in drug-free patients with a history of methamphetamine- or amphetamine-induced psychosis. Stress sensitization associated with noradrenergic hyperactivity and increased dopamine release may be related to this flashbacks. Stressful frightening experiences as well as fear-related paranoid- hallucinatory states during methamphetamine use may be related to these stress sensitization. Robust noradrenergic hyperactivity with increased dopamine release may predicts subsequent flashback episodes. Schizophrenia-like symptoms (e.g., passivity phenomena, Gedankenlautwerden, and thought disorder such as circumstantiality and egorrhea symptoms) appear to develop related to dopaminergic hyperactivity. One of the dopamine receptor-encoding genes DRD2, TaqIA A1/A1 type, with which reduced density of the D2 receptor is associated, reduces to the risk of development of flashbacks. Stress sensitization has been proposed as a key step in the progression from vulnerability to an overt paranoidhallucinatory states, so that schizophrenia and flashbacks due to previous methamphetamine psychosis shares common underlying mechanisms of stress sensitization. Compared to flashbacks due to previous methamphetamine psychosis, psychedelic drug flashbacks are the recurrence of a perception learned while an individual is experiencing high anxiety levels, and thus recur in anxiety-related situations. Anxiety or fear during drug use is an important factor in the development of flashbacks due to previous methamphetamine psychosis and also psychedelic drug flashbacks. Dopaminergic and glutamatergic neural circuits including the striatum, nucleus accumbens and prefrontal cortex play an important role in the development of psychostimulant-induced long-lasting behavioral sensitization. Immediate early genes expression in the particular brain regions affected by the psychostimulants is involved in this process. Furthermore, recent advances in molecular analysis could shed light on the fundamental mechanism involved, by identifying specific participating molecules such as delta FosB, NAC1, G-protein b1 subunit and methamphetamine-responsive transcript 1b.

The present work was conducted to obtain clues for the possible roles of a novel stimulant-inducible gene mrt1 (methamphetamine-responsive transcript 1) encoding a PDZ-PX protein in stimulant-induced behavioral sensitization. In the young adult rats, repeated daily treatment with methamphetamine (4 mg/kg, intraperitoneally, once a day) for 5 days caused an enhanced behavioral response to methamphetamine: behavioral sensitization. The 5-day intermittent administration of MAP upregulated the basal expression of mrt1 transcripts and eliminated the increasing effects of a challenge dose of MAP (1.6 mg/kg, i.p.) or cocaine (30 mg/kg, i.p.) on mrt1 expression on day 14 of withdrawal in the neocortex that has been considered to be composed of a neuron circuit implicated in the sensitization phenomenon. In contrast, the basal expression of other stimulant-inducible and plasticity-related genes arc and homer1a and the ability of MAP or cocaine challenge to augment the amounts of their transcripts were not affected by the repeated MAP regimen in the cortical area. These findings suggest the differential regulation by stimulant of neocortical mrt1, arc, and homer1a expression in the behaviorally sensitized animals and supports the view that stimulant induction of mrt1 may be involved in the early molecular signalings for stimulant sensitization.

We report here the isolation and characterization of cDNA clones for a novel isoform of CDCrel-1 septin, termed CDCrel-1A, with a different 5′ end sequence from the transcripts encoding the known CDCrel-1 (designated as CDCrel-1F) in the developing rat neocortex. Alternative polyadenylation site selections resulted in various transcripts for CDCrel-1A including the fusion forms with another gene, platelet glycoprotein Ibβ (GPIbβ). Expression of the distinct transcripts encoding CDCrel-1A and CDCrel-1F increased and decreased, respectively, from the infant to adult period. Therefore CDCrel-1A might be a major form of the CDCrel-1 septin in the adult neocortex of mammals.

We have studied in the rat the effects of acute subcutaneous injection of psychotomimetics including methamphetamine (MAP), cocaine and phencyclidine (PCP) on the expression of a brain plasticity-related molecule, tissue plasminogen activator (tPA) mRNA, using non-radioactive in situ hybridization histochemistry. In addition to the constitutive expression of tPA mRNA in cerebellar Purkinje cells, ventricular ependymal cells and meningeal blood vessel-associated cells, MAP (1-4 mg/kg), cocaine (30 mg/kg) and PCP (1.25-5 mg/kg) caused a transient and dose-dependent induction of the transcript with its peak at 3 h postinjection in a group of neurons of the medial and insular prefrontal cortices, and the piriform cortex. Another indirect dopamine agonist nomifensine (20-40 mg/kg) mimicked the tPA mRNA induction in the prefrontal cortical areas. Moreover, MAP induction of tPA mRNA was markedly inhibited by pretreatment with a D1 (R(+)-SCH23390: R(+)-7-chloro-8-hydroxy-3-methyl-1-phenyl-2,3,4,5-tetra-hydro-1H-3-be nza zepine hydrochloride) or a D2 (haloperidol) dopamine receptor-preferring antagonist. Intramedial striatum, but not intrathalamic, application of a fluorescent tracer, fluorogold, retrogradely labelled the cortical cells expressing tPA mRNA. The present results suggest that acute injections of the above psychotomimetic drugs may induce tPA mRNA in a group of the prefrontal cortical neurons that project to the medial striatum. This tPA mRNA expression may be due to the activation of the dopamine neurotransmission. Because it is well documented that single or repeated administration of methamphetamine, cocaine and PCP produces enduring changes in responses to these drugs in humans and experimental animals (e.g. behavioural sensitization), the psychotomimetic-induction of tPA mRNA could be implicated in an initial step in the plastic rearrangements in the neuronal circuits underlying long-lasting changes in behavioural expression.

When new learning occurs against the background of established prior knowledge, relevant new information can be assimilated into a schema and thereby expand the knowledge base. An animal model of this important component of memory consolidation reveals that systems memory consolidation can be very fast. In experiments with rats, we found that the hippocampal-dependent learning of new paired associates is associated with a striking up-regulation of immediate early genes in the prelimbic region of the medial prefrontal cortex, and that pharmacological interventions targeted at that area can prevent both new learning and the recall of remotely and even recently consolidated information. These findings challenge the concept of distinct fast (hippocampal) and slow (cortical) learning systems, and shed new light on the neural mechanisms of memory assimilation into schemas.

Context Kynurenic acid, a metabolite of the kynurenine pathway of tryptophan degradation, is an antagonist at N-methyl-D-aspartate andα7 nicotinic acetylcholine receptors and modulates glutamate, dopamine, and acetylcholine signaling. Cortical kynurenic acid concentrations are elevated in the brain and cerebrospinal fluid of schizophrenia patients. The proximal cause may be an impairment of kynurenine 3-monooxygenase (KMO), a rate-limiting enzyme at the branching point of the kynurenine pathway. Objectives To examine KMO messenger RNA expression and KMO enzyme activity in postmortem tissue from the frontal eye field (FEF; Brodmann area 6) obtained from schizophrenia individuals compared with healthy control individuals and to explore the relationship between KMO single-nucleotide polymorphisms and schizophrenia oculomotor endophenotypes. Design Case-control postmortem and clinical study. Setting Maryland Brain Collection, outpatient clinics. Participants Postmortem specimens from schizophrenia patients (n = 32) and control donors (n = 32) and a clinical sample of schizophrenia patients (n = 248) and healthy controls (n = 228). Main Outcome Measures Comparison of quantitative KMO messenger RNA expression and KMO enzyme activity in postmortem FEF tissue between schizophrenia patients and controls and association of KMO single-nucleotide polymorphisms with messenger RNA expression in postmortem FEF and schizophrenia and oculomotor endophenotypes (ie, smooth pursuit eye movements and oculomotor delayed response). Results In postmortem tissue, we found a significant and correlated reduction in KMO gene expression and KMO enzyme activity in the FEF in schizophrenia patients. In the clinical sample, KMO rs2275163 was not associated with a diagnosis of schizophrenia but showed modest effects on predictive pursuit and visuospatial working memory endophenotypes. Conclusion Our results provide converging lines of evidence implicating reduced KMO activity in the etiopathophysiology of schizophrenia and related neurocognitive deficits.

In the mouse hippocampus normal levels of kynurenic acid (KYNA), a neuroactive metabolite synthesized in astrocytes primarily by kynurenine aminotransferase II (KAT II)-catalyzed transamination of l-kynurenine, maintain a degree of tonic inhibition of α7 nicotinic acetylcholine receptors (nAChRs). The present in vitro study was designed to test the hypothesis that α7 nAChR activity decreases when endogenous production of KYNA increases. Incubation (2–7 h) of rat hippocampal slices with kynurenine (200 μM) resulted in continuous de novo synthesis of KYNA. Kynurenine conversion to KYNA was significantly decreased by the KAT II inhibitor (S)-(−)-9-(4-aminopiperazine-1-yl)-8-fluoro-3-methyl-6-oxo-2,3,5,6-tetrahydro-4H-1-oxa-3a-azaphenalene-5carboxylic acid (BFF122) (100 μM) and was more effective in slices from postweaned than preweaned rats. Incubation of slices from postweaned rats with kynurenine inhibited α7 nAChRs and extrasynaptic N-methyl-d-aspartate receptors (NMDARs) on CA1 stratum radiatum interneurons. These effects were attenuated by BFF122 and mimicked by exogenously applied KYNA (200 μM). Exposure of human cerebral cortical slices to kynurenine also inhibited α7 nAChRs. The α7 nAChR sensitivity to KYNA is age-dependent, because neither endogenously produced nor exogenously applied KYNA inhibited α7 nAChRs in slices from preweaned rats. In these slices, kynurenine-derived KYNA also failed to inhibit extrasynaptic NMDARs, which could, however, be inhibited by exogenously applied KYNA. In slices from preweaned and postweaned rats, glutamatergic synaptic currents were not affected by endogenously produced KYNA, but were inhibited by exogenously applied KYNA. These results suggest that in the mature brain α7 nAChRs and extrasynaptic NMDARs are in close apposition to KYNA release sites and, thereby, readily accessible to inhibition by endogenously produced KYNA.

Elucidating the neural and genetic factors underlying psychiatric illness is hampered by current methods of clinical diagnosis. The identification and investigation of clinical endophenotypes may be one solution, but represents a considerable challenge in human subjects. Here we report that mice heterozygous for a null mutation of the alpha-isoform of calcium/calmodulin-dependent protein kinase II (alpha-CaMKII+/-) have profoundly dysregulated behaviours and impaired neuronal development in the dentate gyrus (DG). The behavioral abnormalities include a severe working memory deficit and an exaggerated infradian rhythm, which are similar to symptoms seen in schizophrenia, bipolar mood disorder and other psychiatric disorders. Transcriptome analysis of the hippocampus of these mutants revealed that the expression levels of more than 2000 genes were significantly changed. Strikingly, among the 20 most downregulated genes, 5 had highly selective expression in the DG. Whereas BrdU incorporated cells in the mutant mouse DG was increased by more than 50 percent, the number of mature neurons in the DG was dramatically decreased. Morphological and physiological features of the DG neurons in the mutants were strikingly similar to those of immature DG neurons in normal rodents. Moreover, c-Fos expression in the DG after electric footshock was almost completely and selectively abolished in the mutants. Statistical clustering of human post-mortem brains using 10 genes differentially-expressed in the mutant mice were used to classify individuals into two clusters, one of which contained 16 of 18 schizophrenic patients. Nearly half of the differentially-expressed probes in the schizophrenia-enriched cluster encoded genes that are involved in neurogenesis or in neuronal migration/maturation, including calbindin, a marker for mature DG neurons. Based on these results, we propose that an "immature DG" in adulthood might induce alterations in behavior and serve as a promising candidate endophenotype of schizophrenia and other human psychiatric disorders.

Methamphetamine is a potent and indirect dopaminergic agonist which can cause chronic brain dysfunctions including drug abuse, drug dependence and drug-induced psychosis. Methamphetamine is known to trigger molecular mechanisms involved in associative learning and memory, and thereby alter patterns of synaptic connectivity. The persistent risk of relapse in methamphetamine abuse, dependence and psychosis may be caused by such alterations in synaptic connectivity. EphA5 receptors constitute large families of tyrosine kinase receptor and are expressed almost exclusively in the nervous system, especially in the limbic structures. Recent studies suggest EphA5 to be important in the topographic projection, development, and plasticity of limbic structures, and to be involved in dopaminergic neurotransmission. We used in situ hybridization to examine whether methamphetamine alters EphA5 mRNA expression in the brains of adult male Wister rats. EphA5 mRNA was widely distributed in the medial frontal cortex, cingulate cortex, piriform cortex, hippocampus, habenular nucleus and amygdala. Compared to baseline expression at 0h, EphA5 mRNA was significantly decreased (by 20%) in the medial frontal cortex at 24h, significantly increased (by 30%) in the amygdala at 9 and 24h, significantly but transiently decreased (by 30%) in the habenular nucleus at 1h after a single injection of methamphetamine. Methamphetamine did not change EphA5 mRNA expression in the cingulate cortex, piriform cortex or hippocampus. Our results that methamphetamine altered EphA5 mRNA expression in rat brain suggest methamphetamine could affect patterns of synaptic connectivity, which might be responsible for methamphetamine-induced chronic brain dysfunctions.

Single or repeated exposure to psychostimulants such as amphetamines and cocaine after postnatal week 3 leads to an enduring enhancement in the psychotomimetic responses elicited by a subsequent challenge of a stimulant in rodents. This behavioral sensitization phenomenon has been considered to be the neural consequences of stimulant-induced alterations in gene expression in the brain after a critical period of postnatal development. Using a differential cloning technique, RNA arbitrarily primed PCR, we have now identified from the rat neocortex a novel and developmentally regulated methamphetamine (MAP)-inducible gene mrt1 (MAP responsive transcript 1). mrt1 encodes two major types of PDZ- and PX-domains containing proteins of approximately 62 kDa in size with different carboxy termini, Mrt1a and Mrt1b. The mrt1 mRNAs for Mrt1a, mrt1a, and for Mrt1b, mrt1b, are predominantly expressed in various brain regions and the testes, respectively. Acute MAP injection upregulated mrt1b expression in the neocortex after postnatal week 3 in a D1 receptor antagonist-sensitive manner without affecting mrt1a expression. This upregulation was mimicked by another stimulant, cocaine, whereas pentobarbital and D1 antagonist failed to change the mrt1b transcript levels. Moreover, repeated daily treatment of MAP, but not MAP plus D1 antagonist, for 5 days caused an augmentation of the basal expression of mrt1b 2 and 3 weeks after the drug discontinuation. These late-developing, cocaine-crossreactive, D1 antagonist-sensitive and long-term regulations of mrt1b by MAP are similar to the pharmacological profiles of stimulant-induced behavioral sensitization, and therefore may be associated with the initiation and/or maintenance of the long-term neuronal adaptation.

Experience with amphetamine-like psychostimulants, such as amphetamine, methamphetamine (MAP) or cocaine, results in enhanced neuronal and behavioral responses to subsequent drug exposure. This behavioral sensitization, which is believed to be a part of the mechanisms sustaining drug addiction and drug-induced psychosis in human beings1, is a long-lasting adaptation to drugs of abuse based on persistent cellular and neurochemical changes in some specific brain circuits including the ventral tegmental area (VTA), nucleus accumbens (NAc) and cerebral cortex2. This type of brain plasticity seems to require the gene expression that drives the cascade leading to the establishment and maintenance of the sensitized behavioral responsiveness to stimulants or stress because the application of protein synthesis inhibitors blocks the induction of the sensitization3. Therefore, identification of the stimulant-responsive gene expression that is specifically observed under sensitization-inducing conditions affords helpful clues to understanding the molecular and neuronal mechanism of this unique behavioral plasticity.

To obtain insight into the molecular mechanisms underlying the metabolism and functions of endogenous d-serine, we have explored d-serine-regulated transcripts in the neocortex of the infant rat treated with acute d-serine administration by using an RNA fingerprinting technique. Cloning and sequence analysis of the corresponding cDNAs to the identified transcripts have revealed that the dsr-1 (d-serine responsive transcript-1) mRNA is presumed to contain a novel sequence at the 5'-region, while the 631-base nucleotide sequence of its 3'-end is identical with that of rat M9.2 mRNA encoding a subunit of vacuolar type proton-ATPase. The predicted two open reading frames and their deduced amino acid sequences suggest that the dsr-1 product has a membrane spanning domain. The dsr-1 transcript was detected as a single band around 2.1 kb on the Northern blot. RT-PCR analyses have indicated that the dsr-1 transcript is expressed predominantly in the brain, lung, and testis, and that acute intraperitoneal injection of d-serine significantly upregulates dsr-1 expression in the neocortex 3 and 15 h later without affecting the levels of the M9.2 gene transcript. These results suggest that dsr-1 products may be involved in the d-serine-related metabolic or signaling pathways in mammalian brains.

Identification of genes specifically involved in the establishment of psychostimulant-induced behavioral sensitization is quite important to understand the molecular basis for the pathophysiology of stimulant psychoses. The sensitization is a development-dependent phenomenon and is produced in rats only after postnatal week 3. We, therefore, have explored methamphetamine-regulated transcripts in the neocortex of developing rats (postnatal days 8 and 50) by RNA arbitrarily primed-PCR (RAP-PCR) fingerprinting to identify genes that respond to the drug after the critical period. The bands of the candidate transcripts were cloned, and the expression profile of each RAP-PCR clone was reexamined by semiquantitative RT-PCR accompanying competitive amplification of 285 ribosomal RNA as an internal standard for the assay. Our unique approach based on the developmental aspect of the drug-induced neuroplastic changes should contribute to understanding of the molecular cascade establishing psychostimulant-induced behavioral sensitization.

Protein tyrosine kinases play important roles in the development of the mammalian nervous system during embryogenesis and in the maintenance of function of the adult brain. Using a semi-nested PCR technique based on a short amino acid motif of protein tyrosine kinases, we isolated a human genomic DNA encoding a peptide whose sequence was related to known mammalian protein tyrosine kinases. The expression was examined by Northern blot analysis, and transcripts were detected almost exclusively in the brain. The corresponding cDNA was sequenced, and it was revealed that the gene designated as byk coded for a receptor-like molecule with a motif of protein tyrosine kinase. Immunohistochemical analysis demonstrated that the Byk protein was expressed in neurons and was located in the nuclear envelope. To understand the physiological significance of the Byk protein, we investigated the behavior of this molecule in the hippocampus after ischemia. Byk-like immunoreactivity disappeared from the neurons in the fields CA1 through CA3 and the dentate gurus of the hippocampus following 20 min of ischemia. After recirculation of blood flow, neurons in the CA3 field and the dentate gyrus re-expressed Byk-like antigen but CA1 neurons did not. Interestingly, Byk-like immunoreactivity was detected in microglial cells and astrocytes in the CA1 field that were activated after ischemia. Byk could be a new tool to study the neuron-glia and glia-glia interactions.

Background Previous studies have demonstrated essential roles for alpha-calcium/calmodulin-dependent protein kinase II (alpha-CaMKII) in learning, memory and long-term potentiation (LTP). However, previous studies have also shown that alpha-CaMKII (+/-) heterozygous knockout mice display a dramatic decrease in anxiety-like and fearful behaviors, and an increase in defensive aggression. These findings indicated that alpha-CaMKII is important not only for learning and memory but also for emotional behaviors. In this study, to understand the roles of alpha-CaMKII in emotional behavior, we generated transgenic mice overexpressing alpha-CaMKII in the forebrain and analyzed their behavioral phenotypes. Results We generated transgenic mice overexpressing alpha-CaMKII in the forebrain under the control of the alpha-CaMKII promoter. In contrast to alpha-CaMKII (+/-) heterozygous knockout mice, alpha-CaMKII overexpressing mice display an increase in anxiety-like behaviors in open field, elevated zero maze, light-dark transition and social interaction tests, and a decrease in locomotor activity in their home cages and novel environments; these phenotypes were the opposite to those observed in alpha-CaMKII (+/-) heterozygous knockout mice. In addition, similarly with alpha-CaMKII (+/-) heterozygous knockout mice, alpha-CaMKII overexpressing mice display an increase in aggression. However, in contrast to the increase in defensive aggression observed in alpha-CaMKII (+/-) heterozygous knockout mice, alpha-CaMKII overexpressing mice display an increase in offensive aggression. Conclusion Up-regulation of alpha-CaMKII expression in the forebrain leads to an increase in anxiety-like behaviors and offensive aggression. From the comparisons with previous findings, we suggest that the expression levels of alpha-CaMKII are associated with the state of emotion; the expression level of alpha-CaMKII positively correlates with the anxiety state and strongly affects aggressive behavior.

We have isolated a novel type of mutant strain of Azotobacter vinelandii designated strain WN101 that does not fix nitrogen in the presence of molybdenum but in the presence of tungsten. WN101 produced about twice as much hydrogen as the wild-type strain OP but its production of ethylene from acetylene was less than ten percent of that by OP.