Removing Obstacles in Neuroscience Drug Discovery: The Future Path for Animal Models

Despite great advances in basic neuroscience knowledge, the improved understanding of brain functioning has not yet led to the introduction of truly novel pharmacological approaches to the treatment of central nervous system (CNS) disorders. This situation has been partly attributed to the difficulty of predicting efficacy in patients based on results from preclinical studies. To address these issues, this review critically discusses the traditional role of animal models in drug discovery, the difficulties encountered, and the reasons why this approach has led to suboptimal utilization of the information animal models provide. The discussion focuses on how animal models can contribute most effectively to translational medicine and drug discovery and the changes needed to increase the probability of achieving clinical benefit. Emphasis is placed on the need to improve the flow of information from the clinical/human domain to the preclinical domain and the benefits of using truly translational measures in both preclinical and clinical testing. Few would dispute the need to move away from the concept of modeling CNS diseases in their entirety using animals. However, the current emphasis on specific dimensions of psychopathology that can be objectively assessed in both clinical populations and animal models has not yet provided concrete examples of successful preclinical–clinical translation in CNS drug discovery. The purpose of this review is to strongly encourage ever more intensive clinical and preclinical interactions to ensure that basic science knowledge gained from improved animal models with good predictive and construct validity readily becomes available to the pharmaceutical industry and clinical researchers to benefit patients as quickly as possible.

[1]  David F. Horrobin,et al.  Modern biomedical research: an internally self-consistent universe with little contact with medical reality? , 2003, Nature Reviews Drug Discovery.

[2]  M. Brodie Do we need any more new antiepileptic drugs? , 2001, Epilepsy Research.

[3]  A. Grace,et al.  Developing predictive animal models and establishing a preclinical trials network for assessing treatment effects on cognition in schizophrenia. , 2005, Schizophrenia bulletin.

[4]  R. Freeman,et al.  Neurometabolic coupling in cerebral cortex reflects synaptic more than spiking activity , 2007, Nature Neuroscience.

[5]  T. Insel,et al.  Breaking the log-jam in treatment development for cognition in schizophrenia: NIMH perspective , 2003, Psychopharmacology.

[6]  Y. Lecrubier Refinement of diagnosis and disease classification in psychiatry , 2008, European Archives of Psychiatry and Clinical Neuroscience.

[7]  N. Schork,et al.  Advances in endophenotyping schizophrenia , 2008, World psychiatry : official journal of the World Psychiatric Association.

[8]  David Roblin,et al.  Translational research in the pharmaceutical industry: from bench to bedside. , 2006, Drug discovery today.

[9]  Bruce H. Littman,et al.  The ultimate model organism: progress in experimental medicine , 2005, Nature Reviews Drug Discovery.

[10]  E K Perry,et al.  Correlation of cholinergic abnormalities with senile plaques and mental test scores in senile dementia. , 1978, British medical journal.

[11]  M. Millan,et al.  The Vogel conflict test: procedural aspects, gamma-aminobutyric acid, glutamate and monoamines. , 2003, European journal of pharmacology.

[12]  Nick C Fox,et al.  Amyloid, hypometabolism, and cognition in Alzheimer disease , 2007, Neurology.

[13]  J. Callicott,et al.  Intermediate phenotypes in schizophrenia genetics redux: is it a no brainer? , 2008, Molecular Psychiatry.

[14]  T. Steckler,et al.  Corticotropin-releasing factor receptor antagonists in affective disorders and drug dependence-- an update. , 2006, CNS & neurological disorders drug targets.

[15]  Esther F. Schmid,et al.  Keynote review: Is declining innovation in the pharmaceutical industry a myth? , 2005, Drug discovery today.

[16]  David Gonzales,et al.  Varenicline, an α4β2 Nicotinic Acetylcholine Receptor Partial Agonist, vs Sustained-Release Bupropion and Placebo for Smoking Cessation: A Randomized Controlled Trial , 2006 .

[17]  J. Shields,et al.  Genetic Theorizing and Schizophrenia , 1973, British Journal of Psychiatry.

[18]  G. Dawson,et al.  Use of the elevated plus maze in the search for novel anxiolytic agents. , 1995, Trends in pharmacological sciences.

[19]  M. Geyer The family of sensorimotor gating disorders: Comorbidities or diagnostic overlaps? , 2006, Neurotoxicity Research.

[20]  M. Geyer 33 THE ROLE OF PRECLINICAL MODELS IN THE DEVELOPMENT OF PSYCHOTROPIC DRUGS , 2002 .

[21]  D. DeMets,et al.  Considerations in the evaluation of surrogate endpoints in clinical trials. summary of a National Institutes of Health workshop. , 2001, Controlled clinical trials.

[22]  A. Harrison,et al.  Serotonergic manipulations both potentiate and reduce brain stimulation reward in rats: involvement of serotonin-1A receptors. , 2001, The Journal of pharmacology and experimental therapeutics.

[23]  J. Schildkraut,et al.  The catecholamine hypothesis of affective disorders. A review of supporting evidence. , 1967, International journal of psychiatry.

[24]  J. Crawley,et al.  Behavioral Phenotyping Strategies for Mutant Mice , 2008, Neuron.

[25]  B. Imbimbo Toxicity of β‐amyloid vaccination in patients with Alzheimer's disease , 2002 .

[26]  P P Humphrey,et al.  International Union of Pharmacology classification of receptors for 5-hydroxytryptamine (Serotonin). , 1994, Pharmacological reviews.

[27]  M. Sarter Preclinical research into cognition enhancers. , 2006, Trends in pharmacological sciences.

[28]  Dennis S. Charney,et al.  Neuropsychopharmacology : The Fifth Generation of Progress , 2002 .

[29]  T. Enomoto,et al.  Phencyclidine and genetic animal models of schizophrenia developed in relation to the glutamate hypothesis. , 2007, Methods and findings in experimental and clinical pharmacology.

[30]  S. Mandel,et al.  Novel multifunctional anti-Alzheimer drugs with various CNS neurotransmitter targets and neuroprotective moieties. , 2007, Current Alzheimer research.

[31]  S. Mineka,et al.  Animal Models of Psychopathology , 1991 .

[32]  M. Pangalos,et al.  Drug development for CNS disorders: strategies for balancing risk and reducing attrition , 2007, Nature Reviews Drug Discovery.

[33]  S. Arneric,et al.  Neuronal nicotinic receptors: a perspective on two decades of drug discovery research. , 2007, Biochemical pharmacology.

[34]  D. Schoepp,et al.  Attenuation of specific PCP-evoked behaviors by the potent mGlu2/3 receptor agonist, LY379268 and comparison with the atypical antipsychotic, clozapine , 2000, Psychopharmacology.

[35]  Jason Eriksen,et al.  A decade of modeling Alzheimer's disease in transgenic mice. , 2006, Trends in genetics : TIG.

[36]  Anil K Malhotra,et al.  Ketamine-Induced Exacerbation of Psychotic Symptoms and Cognitive Impairment in Neuroleptic-Free Schizophrenics , 1997, Neuropsychopharmacology.

[37]  A. P. Carobrez,et al.  Ethological and temporal analyses of anxiety-like behavior: The elevated plus-maze model 20 years on , 2005, Neuroscience & Biobehavioral Reviews.

[38]  K. Lundstrom,et al.  Structural genomics and drug discovery , 2007, Journal of cellular and molecular medicine.

[39]  S. Hyman,et al.  Medicine. What are the right targets for psychopharmacology? , 2003, Science.

[40]  J. Streffer,et al.  Transgenic animal models of Alzheimer's disease and related disorders: histopathology, behavior and therapy , 2004, Molecular Psychiatry.

[41]  A. Markou,et al.  Animal models and treatments for addiction and depression co-morbidity , 2009, Neurotoxicity Research.

[42]  R. Porsolt,et al.  Behavioural despair in rats: a new model sensitive to antidepressant treatments. , 1978, European journal of pharmacology.

[43]  Innovation OR Stagnation Challenge and Opportunity on the Critical Path to New Medical Products , 2004 .

[44]  D. Wong,et al.  The Discovery of Fluoxetine Hydrochloride (Prozac) , 2005, Nature Reviews Drug Discovery.

[45]  D. Roblin,et al.  Translational research in the pharmaceutical industry: from theory to reality. , 2007, Drug discovery today.

[46]  I. Kola,et al.  Can the pharmaceutical industry reduce attrition rates? , 2004, Nature Reviews Drug Discovery.

[47]  J Drews,et al.  The role of innovation in drug development. , 1997, Nature biotechnology.

[48]  P. Davies,et al.  SELECTIVE LOSS OF CENTRAL CHOLINERGIC NEURONS IN ALZHEIMER'S DISEASE , 1976, The Lancet.

[49]  A. Hopkins,et al.  The druggable genome , 2002, Nature Reviews Drug Discovery.

[50]  Stephen M Stahl,et al.  Rationale, pharmacology and clinical efficacy of partial agonists of alpha4beta2 nACh receptors for smoking cessation. , 2007, Trends in pharmacological sciences.

[51]  Martin P. Paulus,et al.  A reverse-translational approach to bipolar disorder: Rodent and human studies in the Behavioral Pattern Monitor , 2007, Neuroscience & Biobehavioral Reviews.

[52]  Josemir W Sander,et al.  The excitatory amino acid antagonist d-CPP-ene (SDZ EAA-494) in patients with epilepsy , 1993, Epilepsy Research.

[53]  Craig A. Grimes,et al.  Encyclopedia of Sensors , 2006 .

[54]  B. Poland,et al.  Combining drug-disease and economic modelling to inform drug development decisions. , 2001, Drug discovery today.

[55]  R. Mcarthur,et al.  PREFACE: What Do You Mean by “Translational Research”? An Enquiry Through Animal and Translational Models for CNS Drug Discovery: Reward Deficit Disorders , 2008 .

[56]  I. Kola,et al.  The State of Innovation in Drug Development , 2008, Clinical pharmacology and therapeutics.

[57]  P. Kenny,et al.  Neuroadaptations to chronic exposure to drugs of abuse: Relevance to depressive symptomatology seen across psychiatric diagnostic categories , 2009, Neurotoxicity Research.

[58]  M. Geyer,et al.  New approaches to measurement and treatment research to improve cognition in schizophrenia. , 2005, Schizophrenia bulletin.

[59]  I. Gottesman,et al.  Psychiatric endophenotypes and the development of valid animal models , 2006, Genes, brain, and behavior.

[60]  D. Premack Human and animal cognition: Continuity and discontinuity , 2007, Proceedings of the National Academy of Sciences.

[61]  S. Handley,et al.  Serotonin mechanisms in animal models of anxiety. , 1993, Brazilian journal of medical and biological research = Revista brasileira de pesquisas medicas e biologicas.

[62]  D. Overstreet,et al.  Clinical and biochemical aspects of depressive disorders: II. Transmitter/receptor theories , 1991, Synapse.

[63]  F. Bloom,et al.  Psychopharmacology: The Fourth Generation of Progress , 1995 .

[64]  S. Snyder,et al.  Dopamine receptor binding predicts clinical and pharmacological potencies of antischizophrenic drugs. , 1976, Science.

[65]  A. Halberstadt The phencyclidine-glutamate model of schizophrenia. , 1995, Clinical neuropharmacology.

[66]  W. Fenton,et al.  Measurement and Treatment Research to Improve Cognition in Schizophrenia: NIMH MATRICS initiative to support the development of agents for improving cognition in schizophrenia , 2004, Schizophrenia Research.

[67]  G. Andrews,et al.  Classification of Anxiety and Depressive disorders: problems and solutions , 2008, Depression and anxiety.

[68]  P. Williams The role of pharmacological profiling in safety assessment. , 1990, Regulatory toxicology and pharmacology : RTP.

[69]  B. Imbimbo Toxicity of beta-amyloid vaccination in patients with Alzheimer's disease. , 2002, Annals of neurology.

[70]  N. Rigotti,et al.  Efficacy of varenicline, an alpha4beta2 nicotinic acetylcholine receptor partial agonist, vs placebo or sustained-release bupropion for smoking cessation: a randomized controlled trial. , 2006, JAMA.

[71]  D. Javitt,et al.  Negative schizophrenic symptomatology and the PCP (phencyclidine) model of schizophrenia. , 1987, The Hillside journal of clinical psychiatry.

[72]  G. Rosenbaum,et al.  Study of a new schizophrenomimetic drug; sernyl. , 1959, A.M.A. archives of neurology and psychiatry.

[73]  T. Robbins,et al.  Neurochemical Modulation of Response Inhibition and Probabilistic Learning in Humans , 2006, Science.

[74]  J. Glowinski,et al.  EFFECT OF DRUGS ON THE UPTAKE, RELEASE, AND METABOLISM OF H3-NOREPINEPHRINE IN THE RAT BRAIN. , 1965, The Journal of pharmacology and experimental therapeutics.

[75]  T. Robbins,et al.  Functions of frontostriatal systems in cognition: Comparative neuropsychopharmacological studies in rats, monkeys and humans , 2006, Biological Psychology.

[76]  S. File,et al.  Factors controlling measures of anxiety and responses to novelty in the mouse , 2001, Behavioural Brain Research.

[77]  A. Mortimer Cognitive Function in Schizophrenia— Do Neuroleptics Make a Difference? , 1997, Pharmacology Biochemistry and Behavior.

[78]  D R Medoff,et al.  Ketamine activates psychosis and alters limbic blood flow in schizophrenia , 1995, Neuroreport.

[79]  J. Lieberman,et al.  Methylphenidate and neuroleptic effects on oral word production in schizophrenia , 1992 .

[80]  Nash N. Boutros,et al.  P50 sensory gating ratios in schizophrenics and controls: A review and data analysis , 2008, Psychiatry Research.

[81]  M. Low,et al.  Dopamine D4 Receptor-Knock-Out Mice Exhibit Reduced Exploration of Novel Stimuli , 1999, The Journal of Neuroscience.

[82]  S. Iversen,et al.  Dopamine: 50 years in perspective , 2007, Trends in Neurosciences.

[83]  J. Krystal,et al.  Subanesthetic effects of the noncompetitive NMDA antagonist, ketamine, in humans. Psychotomimetic, perceptual, cognitive, and neuroendocrine responses. , 1994, Archives of general psychiatry.

[84]  T. Robbins,et al.  Inhibitory control in rats performing a stop-signal reaction-time task: effects of lesions of the medial striatum and d-amphetamine. , 2003, Behavioral neuroscience.

[85]  P. Willner Chronic Mild Stress (CMS) Revisited: Consistency and Behavioural-Neurobiological Concordance in the Effects of CMS , 2005, Neuropsychobiology.

[86]  H. Kraemer,et al.  Biomarkers in psychiatry: methodological issues. , 2002, The American journal of geriatric psychiatry : official journal of the American Association for Geriatric Psychiatry.

[87]  J. Tallman Neuropsychopharmacology at the New Millennium: New Industry Directions , 1999, Neuropsychopharmacology.

[88]  T. Robbins,et al.  Early experience as a determinant of adult behavioural responses to reward: the effects of repeated maternal separation in the rat , 2003, Neuroscience & Biobehavioral Reviews.

[89]  M. Geyer Are cross-species measures of sensorimotor gating useful for the discovery of procognitive cotreatments for schizophrenia? , 2006, Dialogues in clinical neuroscience.

[90]  Jason Gong,et al.  Efficacy of Varenicline, an 42 Nicotinic Acetylcholine Receptor Partial Agonist, vs Placebo or Sustained-Release Bupropion for Smoking Cessation A Randomized Controlled Trial , 2006 .

[91]  F. Sams-Dodd Target-based drug discovery: is something wrong? , 2005, Drug discovery today.

[92]  M. Picciotto,et al.  Neuronal Systems Underlying Behaviors Related to Nicotine Addiction: Neural Circuits and Molecular Genetics , 2002, The Journal of Neuroscience.

[93]  T. Feuerstein Presynaptic receptors for dopamine, histamine, and serotonin. , 2008, Handbook of experimental pharmacology.

[94]  Peter Imming,et al.  Drugs, their targets and the nature and number of drug targets , 2007, Nature Reviews Drug Discovery.

[95]  D. Balfour,et al.  Chronic bupropion attenuated the anhedonic component of nicotine withdrawal in rats via inhibition of dopamine reuptake in the nucleus accumbens shell , 2007, The European journal of neuroscience.

[96]  N. Bond Animal models in psychopathology , 1984 .

[97]  J. Crawley Exploratory behavior models of anxiety in mice , 1985, Neuroscience & Biobehavioral Reviews.

[98]  I. Liberzon,et al.  Summary of a National Institute of Mental Health workshop: developing animal models of anxiety disorders , 2001, Psychopharmacology.

[99]  D. Marazziti,et al.  Do animal models of anxiety predict anxiolytic-like effects of antidepressants? , 2002, Psychopharmacology.

[100]  R. Hargreaves,et al.  Clinical biomarkers in drug discovery and development , 2003, Nature Reviews Drug Discovery.

[101]  T. Robbins,et al.  Similar Effects of the Selective Noradrenaline Reuptake Inhibitor Atomoxetine on Three Distinct Forms of Impulsivity in the Rat , 2008, Neuropsychopharmacology.

[102]  M. Lindsay Target discovery , 2003, Nature Reviews Drug Discovery.

[103]  A. Coppen The Biochemistry of Affective Disorders , 1967, British Journal of Psychiatry.

[104]  D. Drachman,et al.  Memory and cognitive function in man , 1977, Neurology.

[105]  L. Iversen,et al.  Neurotransmitter transporters and their impact on the development of psychopharmacology , 2006, British journal of pharmacology.

[106]  Berry M Spruijt,et al.  Advanced behavioural screening: automated home cage ethology. , 2006, Drug discovery today. Technologies.

[107]  C. Morgan,et al.  Acute and chronic effects of ketamine upon human memory: a review , 2006, Psychopharmacology.

[108]  R. Hurst,et al.  Pharmacological profile of the alpha4beta2 nicotinic acetylcholine receptor partial agonist varenicline, an effective smoking cessation aid. , 2007, Neuropharmacology.

[109]  S. B. Caine,et al.  Animal models of drug craving , 2005, Psychopharmacology.

[110]  R. Rodgers,et al.  Ethological comparison of the effects of diazepam and acute/chronic imipramine on the behaviour of mice in the elevated plus-maze , 1995, Pharmacology Biochemistry and Behavior.

[111]  T. Blackburn,et al.  The medical benefit of 5-HT research , 2002, Pharmacology Biochemistry and Behavior.

[112]  Athina Markou,et al.  Assessing antidepressant activity in rodents: recent developments and future needs. , 2002, Trends in pharmacological sciences.

[113]  R. Horowski,et al.  Clinical effects of the neurotropic selective cAMP phosphodiesterase inhibitor rolipram in depressed patients: global evaluation of the preliminary reports , 1985 .

[114]  W. Bunney,et al.  Norepinephrine in depressive reactions. A review. , 1965, Archives of general psychiatry.

[115]  L. Cronbach,et al.  Construct validity in psychological tests. , 1955, Psychological bulletin.

[116]  Opportunities and Challenges of Psychiatric Drug Discovery: Roles for Scientists in Academic, Industry, and Government Settings , 2008, Neuropsychopharmacology.

[117]  A. Cools,et al.  Animal models for the negative symptoms of schizophrenia , 2000, Behavioural pharmacology.

[118]  P. D. De Deyn,et al.  Drug discovery in dementia: the role of rodent models. , 2006, Nature reviews. Drug discovery.

[119]  W. Spooren,et al.  Metabotropic glutamate receptor modulation, translational methods, and biomarkers: relationships with anxiety , 2008, Psychopharmacology.

[120]  G. Koob,et al.  Neurobiological Similarities in Depression and Drug Dependence: A Self-Medication Hypothesis , 1998, Neuropsychopharmacology.

[121]  T. Jay,et al.  A pathophysiological paradigm for the therapy of psychiatric disease , 2005, Nature Reviews Drug Discovery.

[122]  N. Varney,et al.  Psychopharmacology: The Fourth Generation of Progress. , 1996 .

[123]  Michael F. Green,et al.  Identifying Cognitive Mechanisms Targeted for Treatment Development in Schizophrenia: An Overview of the First Meeting of the Cognitive Neuroscience Treatment Research to Improve Cognition in Schizophrenia Initiative , 2008, Biological Psychiatry.

[124]  J. Götz,et al.  Animal models of Alzheimer's disease and frontotemporal dementia , 2008, Nature Reviews Neuroscience.

[125]  E. Jacobsen The early history of psychotherapeutic drugs , 2004, Psychopharmacology.

[126]  A. Harrison,et al.  Paroxetine combined with a 5-HT1A receptor antagonist reversed reward deficits observed during amphetamine withdrawal in rats , 2005, Psychopharmacology.

[127]  M. M. Moraes Anxiogenic-like effect of acute and chronic fluoxetine on rats tested on the elevated plus-maze , 1999 .

[128]  M. Tricklebank The antipsychotic potential of subtype-selective 5-HT receptor ligands based on interactions with mesolimbic dopamine systems , 1995, Behavioural Brain Research.

[129]  E. Bullmore,et al.  Acute Ketamine Administration Alters the Brain Responses to Executive Demands in a Verbal Working Memory Task: an fMRI Study , 2004, Neuropsychopharmacology.

[130]  Solomon Nwaka,et al.  Science & society: Virtual drug discovery and development for neglected diseases through public–private partnerships , 2003, Nature Reviews Drug Discovery.

[131]  Allan Collins,et al.  Behavioral phenotypes of inbred mouse strains: implications and recommendations for molecular studies , 1997, Psychopharmacology.

[132]  M. Brandão,et al.  Acute and Chronic Effects of Gepirone and Fluoxetine in Rats Tested in the Elevated Plus-maze An Ethological Analysis , 2000, Pharmacology Biochemistry and Behavior.

[133]  C. Gorodetzky,et al.  Involving the pharmaceutical and biotech communities in medication development for substance abuse. , 2005, Pharmacology & therapeutics.

[134]  C. Carter,et al.  Cognitive neuroscience-based approaches to measuring and improving treatment effects on cognition in schizophrenia: the CNTRICS initiative. , 2007, Schizophrenia bulletin.

[135]  Robert S. Astur,et al.  Factors affecting the hippocampal BOLD response during spatial memory , 2008, Behavioural Brain Research.

[136]  B. Gallhofer,et al.  Cognitive dysfunction in schizophrenia: comparison of treatment with atypical antipsychotic agents and conventional neuroleptic drugs , 1996, European Neuropsychopharmacology.

[137]  M. Stein,et al.  Developing Novel Anxiolytics: Improving Preclinical Detection and Clinical Assessment , 2008 .

[138]  J. Gogos,et al.  Modeling Madness in Mice: One Piece at a Time , 2006, Neuron.

[139]  S. Rennard,et al.  Varenicline, an alpha4beta2 nicotinic acetylcholine receptor partial agonist, vs sustained-release bupropion and placebo for smoking cessation: a randomized controlled trial. , 2006, JAMA.

[140]  H. Manji,et al.  Cellular Plasticity Cascades: Genes-To-Behavior Pathways in Animal Models of Bipolar Disorder , 2006, Biological Psychiatry.

[141]  D. Javitt,et al.  Recent advances in the phencyclidine model of schizophrenia. , 1991, The American journal of psychiatry.

[142]  D. Westaway,et al.  New developments in animal models of Alzheimer’s disease , 2001, Current neurology and neuroscience reports.

[143]  A. Green Neuropharmacology of 5-hydroxytryptamine. , 2006, British journal of pharmacology.

[144]  Michael F. Green,et al.  Identification of separable cognitive factors in schizophrenia , 2004, Schizophrenia Research.

[145]  R. Lister The use of a plus-maze to measure anxiety in the mouse , 2004, Psychopharmacology.

[146]  A. Markou,et al.  Cognitive-disruptive effects of the psychotomimetic phencyclidine and attenuation by atypical antipsychotic medications in rats , 2007, Psychopharmacology.

[147]  A. Markou,et al.  Characterization of the effects of bupropion on the reinforcing properties of nicotine and food in rats , 2003, Synapse.

[148]  R. Freedman,et al.  Proof-of-concept trial of an alpha7 nicotinic agonist in schizophrenia. , 2006, Archives of general psychiatry.

[149]  D. S. Parker,et al.  A collaborative knowledge base for cognitive phenomics , 2008, Molecular Psychiatry.

[150]  C. Rowe,et al.  Imaging β-amyloid burden in aging and dementia , 2007, Neurology.

[151]  C. Chiamulera,et al.  Nicotinic Receptors and the Treatment of Attentional and Cognitive Deficits in Neuropsychiatric Disorders: Focus on the α7 Nicotinic Acetylcholine Receptor as a Promising Drug Target for Schizophrenia , 2007 .

[152]  D. Javitt,et al.  Neurophysiological biomarkers for drug development in schizophrenia , 2008, Nature Reviews Drug Discovery.

[153]  M. Geyer,et al.  The mGluR5 antagonist MPEP, but not the mGluR2/3 agonist LY314582, augments PCP effects on prepulse inhibition and locomotor activity , 2002, Neuropharmacology.

[154]  G. Velo Erice statement on drug innovation. , 2008, British journal of clinical pharmacology.

[155]  M. Geyer,et al.  Measurement and treatment research to improve cognition in schizophrenia: neuropharmacological aspects , 2004, Psychopharmacology.

[156]  A. S. Freeman,et al.  Relationship between the development of behavioral tolerance and the biodisposition of phencyclidine in mice , 1984, Pharmacology Biochemistry and Behavior.

[157]  D. Skovronsky,et al.  Safety, biodistribution, and dosimetry of 123I-IMPY: a novel amyloid plaque-imaging agent for the diagnosis of Alzheimer's disease. , 2006, Journal of nuclear medicine : official publication, Society of Nuclear Medicine.

[158]  A. Harrison,et al.  Fluoxetine Combined with a Serotonin-1A Receptor Antagonist Reversed Reward Deficits Observed during Nicotine and Amphetamine Withdrawal in Rats , 2001, Neuropsychopharmacology.

[159]  A. Coppen,et al.  Serotonin and its place in the pathogenesis of depression. , 1988, The Journal of clinical psychiatry.

[160]  Herbert Weingartner,et al.  NMDA Receptor Function and Human Cognition: The Effects of Ketamine in Healthy Volunteers , 1996, Neuropsychopharmacology.

[161]  M. Kurt,et al.  The Effects of Sertraline and Fluoxetine on Anxiety in the Elevated Plus-Maze Test , 2000, Journal of basic and clinical physiology and pharmacology.

[162]  A. Holmes Targeted gene mutation approaches to the study of anxiety-like behavior in mice , 2001, Neuroscience & Biobehavioral Reviews.

[163]  C. Hart,et al.  Finding the target after screening the phenotype. , 2005, Drug discovery today.