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Background and Purpose: To follow up in vitro evidence that Delta(9)-tetrahydrocannabivarin extracted from cannabis (eDelta(9)-THCV) is a CB(1) receptor antagonist by establishing whether synthetic Delta(9)-tetrahydrocannabivarin (O-4394) and Delta(8)-tetrahydrocannabivarin (O-4395) behave as CB(1) antagonists in vivo.Experimental Approach: O-4394 and O-4395 were compared with eDelta(9)-THCV as displacers of [(3)H]-CP55940 from specific CB(1) binding sites on mouse brain membranes and as antagonists of CP55940 in [(35)S]GTPgammaS binding assays performed with mouse brain membranes and of R-(+)-WIN55212 in mouse isolated vasa deferentia. Their ability to antagonize in vivo effects of 3 or 10 mg kg(-1) (i.v.) Delta(9)-tetrahydrocannabinol in mice was then investigated.Key Results: O-4394 and O-4395 exhibited similar potencies to eDelta(9)-THCV as displacers of [(3)H]-CP55940 (K (i)=46.6 and 64.4 nM, respectively) and as antagonists of CP55940 in the [(35)S]GTPgammaS binding assay (apparent K (B)=82.1 and 125.9 nM, respectively) and R-(+)-WIN55212 in the vas deferens (apparent K (B)=4.8 and 3.9 nM respectively). At i.v. doses of 0.1, 0.3, 1.0 and/or 3 mg kg(-1) O-4394 and O-4395 attenuated Delta(9)-tetrahydrocannabinol-induced anti-nociception (tail-flick test) and hypothermia (rectal temperature). O-4395 but not O-4394 also antagonized Delta(9)-tetrahydrocannabinol-induced ring immobility. By themselves, O-4395 and O-4394 induced ring immobility at 3 or 10 mg kg(-1) (i.v.) and antinociception at doses above 10 mg kg(-1) (i.v.). O-4395 also induced hypothermia at 3 mg kg(-1) (i.v.) and above.Conclusions and Implications: O-4394 and O-4395 exhibit similar in vitro potencies to eDelta(9)-THCV as CB(1) receptor ligands and as antagonists of cannabinoid receptor agonists and can antagonize Delta(9)-tetrahydrocannabinol in vivo. [ABSTRACT FROM AUTHOR]

Background and purpose:To follow up in vitro evidence that Δ9-tetrahydrocannabivarin extracted from cannabis (eΔ9-THCV) is a CB1 receptor antagonist by establishing whether synthetic Δ9-tetrahydrocannabivarin (O-4394) and Δ8-tetrahydrocannabivarin (O-4395) behave as CB1 antagonists in vivo.Experimental approach:O-4394 and O-4395 were compared with eΔ9-THCV as displacers of [3H]-CP55940 from specific CB1 binding sites on mouse brain membranes and as antagonists of CP55940 in [35S]GTPγS binding assays performed with mouse brain membranes and of R-(+)-WIN55212 in mouse isolated vasa deferentia. Their ability to antagonize in vivo effects of 3 or 10 mg kg−1 (i.v.) Δ9-tetrahydrocannabinol in mice was then investigated.Key results:O-4394 and O-4395 exhibited similar potencies to eΔ9-THCV as displacers of [3H]-CP55940 (K i=46.6 and 64.4 nM, respectively) and as antagonists of CP55940 in the [35S]GTPγS binding assay (apparent K B=82.1 and 125.9 nM, respectively) and R-(+)-WIN55212 in the vas deferens (apparent K B=4.8 and 3.9 nM respectively). At i.v. doses of 0.1, 0.3, 1.0 and/or 3 mg kg−1 O-4394 and O-4395 attenuated Δ9-tetrahydrocannabinol-induced anti-nociception (tail-flick test) and hypothermia (rectal temperature). O-4395 but not O-4394 also antagonized Δ9-tetrahydrocannabinol-induced ring immobility. By themselves, O-4395 and O-4394 induced ring immobility at 3 or 10 mg kg−1 (i.v.) and antinociception at doses above 10 mg kg−1 (i.v.). O-4395 also induced hypothermia at 3 mg kg−1 (i.v.) and above.Conclusions and implications:O-4394 and O-4395 exhibit similar in vitro potencies to eΔ9-THCV as CB1 receptor ligands and as antagonists of cannabinoid receptor agonists and can antagonize Δ9-tetrahydrocannabinol in vivo.British Journal of Pharmacology (2007) 150, 586–594. doi:10.1038/sj.bjp.0707124; published online 22 January 2007 [ABSTRACT FROM AUTHOR]

Presents a study that evaluated whether the endocannabinoid system also plays a role in extinguishing learned escape behavior and spatial memory of mice in a Morris water maze task.

Presents information on a study which investigated the effect of the γ-aminobutyric acid antagonist bicuculline on the Δ9-tetrahydrocannabinol-induced cognitive deficits in mice. Assessment of the disruptive effects of marijuana consumption on learning and memory; Details of statistical analysis; Results.

Rationale: Marijuana remains the most widely used illicit drug in the U.S., and recent attention has been given to putative therapeutic uses of marijuana and cannabinoid derivatives. Thus, developing a better understanding of Δ[sup 9] -THC (tetrahydrocannabinol)-induced mnemonic deficits is of critical importance. Objectives: These experiments were conducted to determine whether Δ[sup 9] -THC has differential effects on spatial reference and working memory tasks, to investigate its receptor mechanism of action, and to compare these effects with those produced by two other compounds – scopolamine and phencyclidine – known to produce mnemonic deficits. In addition, the potency of Δ[sup 9] -THC in these memory tasks was compared with its potency in other pharmacological effects traditionally associated with cannabinoid activity. Methods: Two different versions of the Morris water maze were employed: a working memory task and a reference memory task. Other effects of Δ[sup 9] -THC were assessed using standard tests of hypomotility, antinociception, catalepsy, and hypothermia. Results: Δ[sup 9] -THC disrupted performance of the working memory task (3.0 mg/kg) at doses lower than those required to disrupt performance of the reference memory task (100 mg/kg), or elicit hypomotility, antinociception, catalepsy, and hypothermia. These performance deficits were reversed by SR 141716A. The effects of Δ[sup 9] -THC resembled those of scopolamine, which also selectively disrupted the working maze task. Conversely, phencyclidine disrupted both tasks only at a dose that also produced motor deficits. Conclusions: These data indicate that Δ[sup 9] -THC selectively impairs performance of a working memory task through a CB[sub 1] receptor mechanism of action and that these memory disruptions are more sensitive than other pharmacological effects of Δ[sup 9] -THC. [ABSTRACT FROM AUTHOR]

Introduction: Understanding the immune status of an individual using neutralizing antibody testing is complicated by the continued evolution of the SARS-CoV-2 virus. Previous work showed that assays developed against the wildtype strain of SARS-CoV-2 were insufficient predictors of neutralization of omicron variants, thus we developed an omicron-specific flow cytometry-based neutralizing antibody test and performed experiments to assess how well it compared to an omicron-specific PRNT assay (gold standard) and whether it could predict neutralizing activity to more recent omicron subvariants such as XBB.1.5., Methods: Accuracy of a novel flow cytometry-based neutralizing antibody (FC-NAb) assay was determined by comparison with an omicron-specific PRNT assay. A series of samples were evaluated in both the omicron FC-NAb assay and a second test was designed to assess neutralization of XBB.1.5., Results: Good concordance between the omicron FC-NAb test and the omicron PRNT was demonstrated (AUC = 0.97, p <0.001; sensitivity = 94%, specificity = 100%, PPV = 100%, and NPV = 97%). A strong linear relationship between the omicron FC-NAb and neutralization of XBB1.5 was observed (r = 0.83, p<0.001). Additionally, the omicron FC-NAb test was a very strong predictor of positive XBB1.5 NAb activity (AUC = 0.96, p<0.001; sensitivity = 94%, specificity = 90%, positive predictive value = 90%, and negative predictive values = 94%)., Discussion: Our data suggest that despite continued evolution of the SARS-CoV-2 spike protein, the omicron FC-NAb assay described here is a good predictor of XBB1.5 neutralizing activity, as evidenced by a strong correlation and good predictive performance characteristics., Competing Interests: SV, MG, SN, HL, GC, and SS are all employees and or shareholders of Pearsanta Inc. or its parent company Aditxt Inc. Pearsanta provides clinical laboratory services, including SARS-CoV-2 neutralizing antibody tests. The remaining author declares that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Varvel, Galdzicka, Nystrom, Liu, Chen, Ragan and Shabahang.)

Introduction: Neutralizing antibodies (NAbs) have been recognized as surrogates of protection against SARS-CoV-2; however, the emergence of variants/subvariants escaping neutralization suggests that laboratory assessments of NAbs against the ancestral/wild type (WT) antigens likely overestimate the degree of protection., Methods: A novel flow cytometry-based multiplex test system was developed for the simultaneous detection of NAbs of multiple SARS-CoV-2 variants. SARS-CoV-2 antibodies (Abs) including IgG, IgM, IgA isotypes were measured in the same system. Samples from negative, convalesced, vaccinated, boosted, and breakthrough infection (BTI) populations were tested for both NAbs and Abs., Results: NAbs induced by WT showed neutralization activity that correlated strongly to all variants (R 2 > 0.85) except omicron BA.1/BA.2 (R 2 <0.50). Two doses of vaccine elicited very little protective immunity against BA.1/BA.2, though a booster dose significantly improved NAbs for all variants. NAbs/Abs increased more following BTI than after a booster, suggesting that hybrid immunity (vaccination + natural immunity) was more robust to all variants including BA.1/BA.2. BTIs occurring in the omicron era led to stronger NAb responses against BA.1/BA.2 than did older BTIs. In all comparisons, the RBD antigens demonstrated greater differences between WT and BA.1/BA.2 than the spike antigens., Discussion: Taken together, we demonstrated that both Ab and NAb against multiple SARS-CoV-2 variants/subvariants can be reliably detected on the same multiplex platform. Distinguishing NAbs to the appropriate antigenic target of prevalent variants offers the best correlate of protection and aids individual decisions about the appropriateness and cadence of vaccine boosters and other exposure mitigation strategies., Competing Interests: All authors are employees or stockholders of Aditxt, Inc., which performs the tests described., (Copyright © 2022 Liu, Varvel, Chen, McConnell, Caffrey, Galdzicka and Shabahang.)

People requiring palliative care should have their needs met by services acting in accordance with their wishes. A hospice in the south of England provides such care via a 24/7 hospice at home service. This study aimed to establish how a nurse-led night service supported patients and family carers to remain at home and avoid hospital admissions. Semi-structured interviews were carried out with family carers (n=38) and hospice-at-home staff (n=9). Through night-time phone calls and visits, family carers felt supported by specialist hospice staff whereby only appropriate hospital admission was facilitated. Staff provided mediation between family carer and other services enabling more integrated care and support to remain at home. A hospice-at-home night service can prevent unnecessary hospital admissions and meet patient wishes through specialist care at home.

The cost of visit-based community care based around a 24/7 hospice-at-home (HatH) service in the last 3 months of life was assessed. Thirty families completed a health and social carediary of at-home visits over two-weeks following contact with the HatH night service. Diaries captured 333 days of care provision, averaging 11 diary days per family, 708 health care professional and carer visits, lasting 604 hours at a cost of £20,192 ($24,946). Hat H care, integrated with community support, seems an economic proposition but highlights the complexities of assessing cost of end of life care.

Objective: The MHC region harbors the strongest loci for latent autoimmune diabetes in adults (LADA); however, the strength of association is likely attenuated compared with that for childhood-onset type 1 diabetes. In this study, we recapitulate independent effects in the MHC class I region in a population with type 1 diabetes and then determine whether such conditioning in LADA yields potential genetic discriminators between the two subtypes within this region., Research Design and Methods: Chromosome 6 was imputed using SNP2HLA, with conditional analysis performed in type 1 diabetes case subjects ( n = 1,985) and control subjects ( n = 2,219). The same approach was applied to a LADA cohort ( n = 1,428) using population-based control subjects ( n = 2,850) and in a separate replication cohort (656 type 1 diabetes case, 823 LADA case, and 3,218 control subjects)., Results: The strongest associations in the MHC class II region (rs3957146, β [SE] = 1.44 [0.05]), as well as the independent effect of MHC class I genes, on type 1 diabetes risk, particularly HLA-B*39 (β [SE] = 1.36 [0.17]), were confirmed. The conditional analysis in LADA versus control subjects showed significant association in the MHC class II region (rs3957146, β [SE] = 1.14 [0.06]); however, we did not observe significant independent effects of MHC class I alleles in LADA., Conclusions: In LADA, the independent effects of MHC class I observed in type 1 diabetes were not observed after conditioning on the leading MHC class II associations, suggesting that the MHC class I association may be a genetic discriminator between LADA and childhood-onset type 1 diabetes., (© 2019 by the American Diabetes Association.)

Objective: Latent autoimmune diabetes in adults (LADA) shares clinical features with both type 1 and type 2 diabetes; however, there is ongoing debate regarding the precise definition of LADA. Understanding its genetic basis is one potential strategy to gain insight into appropriate classification of this diabetes subtype., Research Design and Methods: We performed the first genome-wide association study of LADA in case subjects of European ancestry versus population control subjects ( n = 2,634 vs. 5,947) and compared against both case subjects with type 1 diabetes ( n = 2,454 vs. 968) and type 2 diabetes ( n = 2,779 vs. 10,396)., Results: The leading genetic signals were principally shared with type 1 diabetes, although we observed positive genetic correlations genome-wide with both type 1 and type 2 diabetes. Additionally, we observed a novel independent signal at the known type 1 diabetes locus harboring PFKFB3 , encoding a regulator of glycolysis and insulin signaling in type 2 diabetes and inflammation and autophagy in autoimmune disease, as well as an attenuation of key type 1-associated HLA haplotype frequencies in LADA, suggesting that these are factors that distinguish childhood-onset type 1 diabetes from adult autoimmune diabetes., Conclusions: Our results support the need for further investigations of the genetic factors that distinguish forms of autoimmune diabetes as well as more precise classification strategies., (© 2018 by the American Diabetes Association.)

Objective: Elevated lipoprotein(a) [Lp(a)] is a causal, independent risk factor for cardiovascular disease and aortic stenosis. We aimed to define the prevalence and patient thresholds of elevated Lp(a) levels in the United States., Approach and Results: We analyzed Lp(a) levels in 532 359 subjects from 2 data sets: (1) in 531 144 subjects from a referral laboratory and (2) in 915 patients from a tertiary referral center. Lp(a) mass levels were measured by immunoturbidometric assays in both centers and expressed as mg/dL. At the referral laboratory, the median age (interquartile range) of the subjects was 57.0 (46-67) years, and 51.9% were female. Lp(a) levels were skewed rightward as expected. The mean±SD levels were 34.0±40.0 mg/dL, and median (interquartile range) levels were 17 (7-47) mg/dL, with range 0 to 907 mg/dL. Lp(a) levels at 75%, 80%, 90%, 95%, 99%, and 99.9% percentiles were >47, >60, >90, >116, >180, and >245 mg/dL, respectively. At the referral laboratory, Lp(a) levels >30 and >50 mg/dL were present in 35.0% and 24.0% of subjects, respectively, and at the tertiary referral center, 39.5% and 29.2%, respectively. Females had higher mean (SD) (37.0 [42.7] versus 30.7 [36.7]; P<0.0001) and median (interquartile range) (19 [8-53] versus 15 [7-42]; P<0.0001) Lp(a) than males., Conclusions: This is the largest database to assess the distribution of Lp(a) and is derived from patients as opposed to general populations. Lp(a) levels >30 and >50 mg/dL were fairly common, particularly in a tertiary care setting. These data may inform consensus documents, guidelines, and therapeutic cutoffs for Lp(a)-mediated cardiovascular risk., (© 2016 American Heart Association, Inc.)

Big data and advances in analytical processes represent an opportunity for the healthcare industry to make better evidence-based decisions on the value generated by various tests, procedures, and interventions. Value-based reimbursement is the process of identifying and compensating healthcare providers based on whether their services improve quality of care without increasing cost of care or maintain quality of care while decreasing costs. In this article, we motivate and illustrate the potential opportunities for payers and providers to collaborate and evaluate the clinical and economic efficacy of different healthcare services. We conduct a case study of a firm that offers advanced biomarker and disease state management services for cardiovascular and cardiometabolic conditions. A value-based analysis that comprised a retrospective case/control cohort design was conducted, and claims data for over 7000 subjects who received these services were compared to a matched control cohort. Study subjects were commercial and Medicare Advantage enrollees with evidence of CHD, diabetes, or a related condition. Analysis of medical claims data showed a lower proportion of patients who received biomarker testing and disease state management services experienced a MI (p < 0.01) or diabetic complications (p < 0.001). No significant increase in cost of care was found between the two cohorts. Our results illustrate the opportunity healthcare payers such as Medicare and commercial insurance companies have in terms of identifying value-creating healthcare interventions. However, payers and providers also need to pursue system integration efforts to further automate the identification and dissemination of clinically and economically efficacious treatment plans to ensure at-risk patients receive the treatments and interventions that will benefit them the most.

Earlier reports indicated that patients with the apolipoprotein APOE ε4 allele responded to fish oil supplementation with a rise in serum low-density lipoprotein cholesterol (LDL-C) compared to ε3 homozygotes. In this study, we used clinical laboratory data to test the hypothesis that the cross-sectional relation between RBC omega-3 fatty acid status (the Omega-3 Index) and LDL-C was modified by APOE genotype. Data from 136,701 patients were available to compare lipid biomarker levels across Omega-3 Index categories associated with heart disease risk in all APOE genotypes. We found no adverse interactions between APOE genotype and the Omega-3 Index for LDL-C, LDL particle number, apoB, HDL-C, or triglycerides. However, we did find evidence that ε2 homozygotes lack an association between omega-3 status and LDL-C, apoB, and LDL particle number. In summary, we found no evidence for a deleterious relationship between lipid biomarkers and the Omega-3 Index by APOE genotype.

In an effort to reduce cost and improve quality, health care payers have enacted a number of incentives to motivate providers to focus their efforts on achieving better clinical outcomes and reducing the prevalence and progression of disease. In response to these incentives, providers are entering into new arrangements such as accountable care organizations and patient-centered medical homes to redesign delivery processes and achieve quality and cost objectives. This article reports the results of a study designed to evaluate the impact on cost and quality of care resulting from services provided by Health Diagnostic Laboratory, Inc., a clinical laboratory with a comprehensive care model. The results show that patients who utilized these laboratory services experienced lower total cost of care (23% reduction, P<0.01) and improved lipid profiles during the follow-up period. Total cost reductions were related to cost reductions found in both inpatient and ambulatory care. These findings suggest that accountable care organizations, patient-centered medical homes, and other groups entering shared savings initiatives should consider the potential role ancillary service providers with comprehensive care models can play in the delivery of integrated care.

Objectives: To compare biopsy quality factors among study sites worldwide at entry and at year 2 in the reduction by dutasteride of prostate cancer events study. The accuracy of prostate cancer detection is influenced by the length and number of biopsy cores., Methods: Biopsy quality factors at entry and at year 2 were compared for subjects enrolled from 6 geographic regions: North America, South America, Western Europe, Central/Eastern Europe, Australia, and Africa. Investigator training was provided for prostate biopsy collection before year 2, emphasizing core length and number of cores obtained., Results: Data were collected prospectively from 4649 subjects at entry and 6267 subjects at year 2. At entry, the aggregate length, number of cores, and mean length of cores differed significantly among regions. Aggregate length was longest in biopsies from Australia, and number of cores was highest from South America. At year 2, each region collected the protocol-required 10 cores, and aggregate length and mean length of cores were greater than for entry biopsies; site variance was reduced for all factors., Conclusions: There were significant differences in aggregate length, number of cores, and mean length of cores among regions at study entry. After investigator training by the study sponsor and use of a central laboratory for standardized processing, year 2 biopsies showed an increase in all 3 quality factors when compared with entry biopsies. Variance in biopsy quality can be reduced by investigator training and standardization of collection and processing, thereby optimizing detection of cancer. Biopsy quality may be a useful comparative measure in urologic practice., (Copyright (c) 2010 Elsevier Inc. All rights reserved.)

Rationale: The results of recent in vitro studies have underscored the important role that activation of CB(1) receptors has on GABAergic activity in brain areas associated with memory., Objectives: The primary purpose of this study was to test the hypothesis that the memory disruptive effects of Delta(9)-tetrahydrocannabinol (Delta(9)-THC) in vivo are mediated through GABAergic systems. Conversely, we also evaluated whether blocking CB(1) receptor signaling would alter memory deficits elicited by GABA agonists., Methods: The GABA(A) antagonist bicuculline and GABA(B) antagonist CGP 36742 were evaluated for their ability to ameliorate Delta(9)-THC-induced deficits in a mouse working memory Morris water maze task. Mice were also assessed in a T-maze task, as well as non-cognitive behavioral assays. Additionally, the effects of GABA(A) and GABA(B) agonists were assessed in either CB(1) (-/-) mice or wild type mice treated with the CB(1) antagonist SR 141716., Results: Memory deficits resulting from 10 mg/kg Delta(9)-THC in the Morris water maze were completely reversed by bicuculline, though unaffected by CGP 36742. Bicuculline also blocked the disruptive effects of Delta(9)-THC in the T-maze, but failed to alter non-mnemonic effects of Delta(9)-THC. Although CB(1) (-/-) mice exhibited supersensitivity to muscimol-induced water maze deficits compared with wild type control mice, muscimol elicited virtually identical effects in SR 141716-treated and vehicle-treated wild type mice., Conclusions: This is the first demonstration of which we are aware showing that GABA(A) receptors may play a necessary role in Delta(9)-THC-induced memory impairment in whole animals.

Cannabis use is associated with a wide range of pharmacological effects, some of which have potential therapeutic benefit while others result in negative outcomes. Acute cannabinoid intoxication has been well documented to produce deficits in cognitive functioning with concomitant changes in glutamatergic, GABAergic, and cholinergic neurochemical systems in the hippocampus, each of which has been implicated in memory. Additionally, cannabis-dependent individuals abstaining from this drug can undergo a constellation of mild withdrawal effects. The use of the CB(1) cannabinoid receptor antagonist SR141716A and transgenic mice lacking the CB(1) receptor are critical tools for investigating the role of the endocannabinoid system in cognition, drug dependence, and other physiological processes. Converging evidence in which performance in a variety of memory tasks is enhanced following either SR141716A treatment or in CB(1) receptor knockout mice indicates that this system may play an important role in modulating cognition. There are also indications that this system may function to modulate opioid dependence. The purpose of this review is to describe recent advances that have furthered our understanding of the roles that the endocannabinoid system play on both cognition and drug dependence., (Copyright 2002 Published by Elsevier Science Ltd.)

Previous research conducted in this and other laboratories has examined the role of genetic factors in determining sensitivity to (-)-nicotine in a variety of behavioral and physiological measures in the rat. More recent research further indicates that genetic factors can also influence the level of sensitivity to (-)-nicotine when serving as a discriminative stimulus (DS) in different rat strains. However, there has been little work examining the influence of genotype on the discriminative stimulus (DS) properties of (-)-nicotine in mice, a species that has played a major role in understanding the relationship between genetics and (-)-nicotine pharmacological effects. To further our understanding of the role of genetics and the ability of (-)-nicotine to exert DS control of behavior in the mouse, a group of C57BL/6 mice was trained to discriminate 0.4 mg/kg (-)-nicotine from saline using a two-lever operant procedure. (-)-Nicotine's discriminative stimulus in C57BL/6 mice appears to be similar to that generated in the rat. Results from behavioral tests with other drugs indicated that d-amphetamine exhibited a partial generalization, while (+)-nicotine fully generalized with nicotine. Tests of antagonism with mecamylamine and scopolamine further showed the cholinergic specificity of the (-)-nicotine DS in the mouse; mecamylamine but not scopolamine completely antagonized the (-)-nicotine DS. This work lays the groundwork for future comparisons of different mouse strain's sensitivities to (-)-nicotine's discriminative stimulus as well as using this behavioral model to search for new nicotinic receptor agonists and antagonists.

N-Methyl-D-aspartate (NMDA) antagonists and gamma-aminobutyric acid agonists share a number of common pharmacological properties, including motor and anticonvulsant effects. In the present study, site-selective NMDA antagonists were evaluated for potential anxiolytic efficacy and motor impairment in a modified Geller-Seifter conflict procedure, an animal model widely used to screen drugs for anxiolytic effects. Male Sprague-Dawley rats were trained to respond for food reward under a multiple FI 30 s (food only), FR 10 (food + shock) operant schedule. Consistent with the results of previous studies, the benzodiazepines chlordiazepoxide and diazepam selectively increased punished responding and increased response durations at higher doses. The competitive NMDA antagonist CGP 37,849 increased punished responding at some doses, though not selectively, and also increased response duration in both schedule components. The glycine-site modulators milacemide, ACEA 1011 and ACEA 1021, the NR2B-selective polyamine site antagonist eliprodil and NMDA did not produce anticonflict effects at any dose and had inconsistent effects on response durations. These results suggest that the anticonflict effects of NMDA antagonists are not as reliable as those of the benzodiazepines. Further research is needed to clarify the experimental conditions under which the anxiolytic potential of NMDA antagonists is most evident.