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Ding Z, Ejendal KFK, Soto-Velasquez M, Hayes MP, Santoro N, Larsen MJ, Watts VJ. Genome-Wide Small Interfering RNA Screening Reveals a Role for Cullin3-Really Interesting New Gene Ligase Signaling in Heterologous Sensitization of Adenylyl Cyclase. J Pharmacol Exp Ther 2019; 372:267-276. [PMID: 31857349 DOI: 10.1124/jpet.119.261255] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2019] [Accepted: 12/12/2019] [Indexed: 12/18/2022] Open
Abstract
Heterologous sensitization of adenylyl cyclase (AC) is revealed as enhanced or exaggerated AC/cAMP signaling that occurs following persistent activation of Gα i/o-coupled receptors. This paradoxical phenomenon was discovered more than 40 years ago and was proposed as a cellular mechanism to explain the adaptive changes that occur following chronic exposure to drugs of abuse. However, the underlying molecular mechanisms of heterologous sensitization of AC remain largely unknown. In the present study, we performed a genome-wide cell-based RNA interference screen as an unbiased approach to identify genes associated with heterologous sensitization of AC. Following a series of validation and confirmation assays, three genes that form an E3 ligase complex, cullin3 (CUL3), neural precursor-cell-expressed and developmentally downregulated 8 (NEDD8), and really interesting new gene (RING)-box protein 1 (RBX1), were identified as specific modulators of heterologous sensitization of AC. Furthermore, based on the downstream actions of these genes, we evaluated the activity of proteasome inhibitors as well as the specific NEDD8-activating enzyme inhibitor, MLN4924 (Pevonedistat), in AC sensitization. We demonstrate that MG-132 and bortezomib treatments could mimic the inhibitory effects observed with gene knockdown, and MLN4924 was potent and efficacious in blocking the development of heterologous sensitization of endogenous and recombinant AC isoforms, including AC1, AC2, AC5, and AC6. Together, by using genetic and pharmacological approaches, we identified, for the first time, cullin3-RING ligases and the protein degradation pathway as essential modulators for heterologous sensitization of AC. SIGNIFICANCE STATEMENT: Through a genome-wide cell-based RNA interference screening, we identified three genes that form an E3 ligase complex, cullin3, neural precursor-cell-expressed and developmentally downregulated 8 (NEDD8), and really interesting new gene-box protein 1, as specific modulators of heterologous sensitization of AC. The effect of cullin3, NEDD8, or really interesting new gene-box protein 1 small interfering RNAs on heterologous sensitization was recapitulated by proteasome inhibitors, MG132 and bortezomib, and the specific NEDD8-activating enzyme inhibitor, MLN4924. These results suggest a novel hypothesis in which protein degradation is involved in the sensitization of AC signaling that occurs following chronic activation of Gαi/o-coupled receptors.
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Affiliation(s)
- Zhong Ding
- Department of Medicinal Chemistry and Molecular Pharmacology (Z.D., K.F.K.E., M.S.-V., M.P.H., V.J.W.), Purdue Institute for Drug Discovery (V.J.W.), and Purdue Institute for Integrative Neuroscience (V.J.W.), Purdue University, West Lafayette, Indiana; and Center for Chemical Genomics, University of Michigan, Ann Arbor, Michigan (N.S., M.J.L.)
| | - Karin F K Ejendal
- Department of Medicinal Chemistry and Molecular Pharmacology (Z.D., K.F.K.E., M.S.-V., M.P.H., V.J.W.), Purdue Institute for Drug Discovery (V.J.W.), and Purdue Institute for Integrative Neuroscience (V.J.W.), Purdue University, West Lafayette, Indiana; and Center for Chemical Genomics, University of Michigan, Ann Arbor, Michigan (N.S., M.J.L.)
| | - Monica Soto-Velasquez
- Department of Medicinal Chemistry and Molecular Pharmacology (Z.D., K.F.K.E., M.S.-V., M.P.H., V.J.W.), Purdue Institute for Drug Discovery (V.J.W.), and Purdue Institute for Integrative Neuroscience (V.J.W.), Purdue University, West Lafayette, Indiana; and Center for Chemical Genomics, University of Michigan, Ann Arbor, Michigan (N.S., M.J.L.)
| | - Michael P Hayes
- Department of Medicinal Chemistry and Molecular Pharmacology (Z.D., K.F.K.E., M.S.-V., M.P.H., V.J.W.), Purdue Institute for Drug Discovery (V.J.W.), and Purdue Institute for Integrative Neuroscience (V.J.W.), Purdue University, West Lafayette, Indiana; and Center for Chemical Genomics, University of Michigan, Ann Arbor, Michigan (N.S., M.J.L.)
| | - Nicholas Santoro
- Department of Medicinal Chemistry and Molecular Pharmacology (Z.D., K.F.K.E., M.S.-V., M.P.H., V.J.W.), Purdue Institute for Drug Discovery (V.J.W.), and Purdue Institute for Integrative Neuroscience (V.J.W.), Purdue University, West Lafayette, Indiana; and Center for Chemical Genomics, University of Michigan, Ann Arbor, Michigan (N.S., M.J.L.)
| | - Martha J Larsen
- Department of Medicinal Chemistry and Molecular Pharmacology (Z.D., K.F.K.E., M.S.-V., M.P.H., V.J.W.), Purdue Institute for Drug Discovery (V.J.W.), and Purdue Institute for Integrative Neuroscience (V.J.W.), Purdue University, West Lafayette, Indiana; and Center for Chemical Genomics, University of Michigan, Ann Arbor, Michigan (N.S., M.J.L.)
| | - Val J Watts
- Department of Medicinal Chemistry and Molecular Pharmacology (Z.D., K.F.K.E., M.S.-V., M.P.H., V.J.W.), Purdue Institute for Drug Discovery (V.J.W.), and Purdue Institute for Integrative Neuroscience (V.J.W.), Purdue University, West Lafayette, Indiana; and Center for Chemical Genomics, University of Michigan, Ann Arbor, Michigan (N.S., M.J.L.)
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Servaes S, Glorie D, Stroobants S, Staelens S. Neuroreceptor kinetics in rats repeatedly exposed to quinpirole as a model for OCD. PLoS One 2019; 14:e0213313. [PMID: 30845202 PMCID: PMC6405120 DOI: 10.1371/journal.pone.0213313] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2018] [Accepted: 02/19/2019] [Indexed: 11/24/2022] Open
Abstract
Background Obsessive-compulsive disorder (OCD) is a chronic, incapacitating, early onset psychiatric disorder that is characterized by obsessions and compulsions originating from a disturbance in the cortico-striato-thalamico-cortical circuit. We implemented the preclinical quinpirole (QP) rat model for compulsive checking in OCD to analyse the behaviour and visualize the D2R, mGluR5 and GLT1 density in order to contribute to the understanding of the neuroreceptor kinetics. Methods Animals (n = 14) were exposed to either saline (1 mL/kg) or QP (dopamine D2-agonist, 0.5 mg/kg) twice-weekly during 7 weeks. After each injection animals were placed on an open field test. After model setup, animals were placed in a behavioural cage equipped with tracking software and hardware in order to analyse the behaviour. Subsequently, sagittal slides were made of the CP in the right hemisphere and a staining was done with the D2R, mGluR5 and GLT-1 antibody to visualize the corresponding receptor. Results The QP animals displayed a strong increase in travelled distance (+596.70%) and in the number of homebase visits (+1222.90%) compared to the control animals. After chronic exposure to QP, animals had a significantly (p < 0.05) higher percentage of D2R density in the CP (7.92% ± 0.48%) versus 6.66% ± 0.28% in animals treated with saline. There were no differences for mGluR5 and GLT1 receptor density. Conclusions Chronic exposure to QP leads to hyperlocomotion and an increase in D2R density. Furthermore, as mGluR5 and GLT1 density did not seem to be directly affected, decreased levels of glutamate might have influenced the binding potential in earlier reports.
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Affiliation(s)
- Stijn Servaes
- Molecular Imaging Center Antwerp (MICA), University of Antwerp, Wilrijk, Antwerp, Belgium
| | - Dorien Glorie
- Molecular Imaging Center Antwerp (MICA), University of Antwerp, Wilrijk, Antwerp, Belgium
| | - Sigrid Stroobants
- Molecular Imaging Center Antwerp (MICA), University of Antwerp, Wilrijk, Antwerp, Belgium
- Department of Nuclear Medicine, University Hospital Antwerp, Edegem, Antwerp, Belgium
| | - Steven Staelens
- Molecular Imaging Center Antwerp (MICA), University of Antwerp, Wilrijk, Antwerp, Belgium
- * E-mail:
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Brust TF, Conley JM, Watts VJ. Gα(i/o)-coupled receptor-mediated sensitization of adenylyl cyclase: 40 years later. Eur J Pharmacol 2015; 763:223-32. [PMID: 25981304 DOI: 10.1016/j.ejphar.2015.05.014] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2015] [Revised: 03/02/2015] [Accepted: 05/11/2015] [Indexed: 12/20/2022]
Abstract
Heterologous sensitization of adenylyl cyclase (also referred to as superactivation, sensitization, or supersensitization of adenylyl cyclase) is a cellular adaptive response first described 40 years ago in the laboratory of Dr. Marshall Nirenberg. This apparently paradoxical cellular response occurs following persistent activation of Gαi/o-coupled receptors and causes marked enhancement in the activity of adenylyl cyclases, thereby increasing cAMP production. Since our last review in 2005, significant progress in the field has led to a better understanding of the relevance of, and the cellular biochemical processes that occur during the development and expression of heterologous sensitization. In this review we will discuss the recent advancements in the field and the mechanistic hypotheses on heterologous sensitization.
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Affiliation(s)
- Tarsis F Brust
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, 575 Stadium Mall Drive, West Lafayette, IN 47907, USA
| | - Jason M Conley
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, 575 Stadium Mall Drive, West Lafayette, IN 47907, USA
| | - Val J Watts
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, 575 Stadium Mall Drive, West Lafayette, IN 47907, USA.
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Brust TF, Hayes MP, Roman DL, Watts VJ. New functional activity of aripiprazole revealed: Robust antagonism of D2 dopamine receptor-stimulated Gβγ signaling. Biochem Pharmacol 2014; 93:85-91. [PMID: 25449598 DOI: 10.1016/j.bcp.2014.10.014] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2014] [Revised: 10/29/2014] [Accepted: 10/30/2014] [Indexed: 01/11/2023]
Abstract
The dopamine D2 receptor (DRD2) is a G protein-coupled receptor (GPCR) that is generally considered to be a primary target in the treatment of schizophrenia. First generation antipsychotic drugs (e.g. haloperidol) are antagonists of the DRD2, while second generation antipsychotic drugs (e.g. olanzapine) antagonize DRD2 and 5HT2A receptors. Notably, both these classes of drugs may cause side effects associated with D2 receptor antagonism (e.g. hyperprolactemia and extrapyramidal symptoms). The novel, "third generation" antipsychotic drug, aripiprazole is also used to treat schizophrenia, with the remarkable advantage that its tendency to cause extrapyramidal symptoms is minimal. Aripiprazole is considered a partial agonist of the DRD2, but it also has partial agonist/antagonist activity for other GPCRs. Further, aripiprazole has been reported to have a unique activity profile in functional assays with the DRD2. In the present study the molecular pharmacology of aripiprazole was further examined in HEK cell models stably expressing the DRD2 and specific isoforms of adenylyl cyclase to assess functional responses of Gα and Gβγ subunits. Additional studies examined the activity of aripiprazole in DRD2-mediated heterologous sensitization of adenylyl cyclase and cell-based dynamic mass redistribution (DMR). Aripiprazole displayed a unique functional profile for modulation of G proteins, being a partial agonist for Gαi/o and a robust antagonist for Gβγ signaling. Additionally, aripiprazole was a weak partial agonist for both heterologous sensitization and dynamic mass redistribution.
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Affiliation(s)
- Tarsis F Brust
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, 575 Stadium Mall Drive, West Lafayette, IN - 47907, United States
| | - Michael P Hayes
- Department of Pharmaceutical Sciences and Experimental Therapeutics, University of Iowa - 115 S. Grand Ave, Iowa City, IA - 52242, United States
| | - David L Roman
- Department of Pharmaceutical Sciences and Experimental Therapeutics, University of Iowa - 115 S. Grand Ave, Iowa City, IA - 52242, United States
| | - Val J Watts
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, 575 Stadium Mall Drive, West Lafayette, IN - 47907, United States.
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Shannonhouse JL, York DC, Morgan C. A modified anxious behavior test for hamsters. J Neurosci Methods 2014; 221:62-9. [DOI: 10.1016/j.jneumeth.2013.09.013] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2013] [Revised: 09/18/2013] [Accepted: 09/21/2013] [Indexed: 10/26/2022]
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Hyer MM, Rycek LM, Floody OR. Effects of apomorphine on mating behavior, flank marking and aggression in male hamsters. Pharmacol Biochem Behav 2012; 101:520-7. [DOI: 10.1016/j.pbb.2012.02.019] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/29/2011] [Revised: 02/19/2012] [Accepted: 02/26/2012] [Indexed: 10/28/2022]
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Dopamine D(2) Receptor-Mediated Heterologous Sensitization of AC5 Requires Signalosome Assembly. JOURNAL OF SIGNAL TRANSDUCTION 2012; 2012:210324. [PMID: 22523680 PMCID: PMC3317181 DOI: 10.1155/2012/210324] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/07/2011] [Accepted: 12/28/2011] [Indexed: 12/23/2022]
Abstract
Chronic dopamine receptor activation is implicated in several central nervous system disorders. Although acute activation of Gαi-coupled D2 dopamine receptors inhibits adenylyl cyclase, persistent activation enhances adenylyl cyclase activity, a phenomenon called heterologous sensitization. Previous work revealed a requirement for Gαs in D2-induced heterologous sensitization of AC5. To elucidate the mechanism of Gαs dependency, we expressed Gαs mutants in Gαs-deficient GnasE2−/E2−
cells. Neither Gαs-palmitoylation nor Gαs-Gβγ interactions were required for sensitization of AC5. Moreover, we found that coexpressing βARKct-CD8 or Sar1(H79G) blocked heterologous sensitization. These studies are consistent with a role for Gαs-AC5 interactions in sensitization however, Gβγ appears to have an indirect role in heterologous sensitization of AC5, possibly by promoting proper signalosome assembly.
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Triana-Del Rio R, Montero-Domínguez F, Cibrian-Llanderal T, Tecamachaltzi-Silvaran MB, Garcia LI, Manzo J, Hernandez ME, Coria-Avila GA. Same-sex cohabitation under the effects of quinpirole induces a conditioned socio-sexual partner preference in males, but not in female rats. Pharmacol Biochem Behav 2011; 99:604-13. [PMID: 21704064 DOI: 10.1016/j.pbb.2011.06.006] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/15/2011] [Revised: 05/30/2011] [Accepted: 06/06/2011] [Indexed: 10/18/2022]
Abstract
The effects of the dopamine D2-type receptor agonist quinpirole (QNP) were examined on the development of conditioned same-sex partner preference induced by cohabitation in rats. In Experiment 1, males received either saline or QNP (1.25mg/kg) and cohabited during three trials with almond-scented stimulus males that were sexually naïve. In Experiment 2, males received six trials, and in Experiment 3 received three trials with sexually expert stimulus males. During a final drug-free preference test, males chose between the familiar or a novel male partner. In Experiments 1, 2 and 3 only QNP-treated males displayed a social preference for the familiar male, observed with more time spent together. In Experiment 3 males also displayed a sexual preference observed with more non-contact erections when were exposed to their male partner. In Experiment 4 we tested the effects on OVX, E+P primed females that received 1 systemic injection of either saline or QNP during three conditioning trials. In Experiment 5, females received 2 injections 12-h apart during each trial. Results indicated that both saline and QNP-treated females failed to develop partner preference. These data demonstrate that enhanced D2-type receptor activity during cohabitation facilitates the development of conditioned same-sex partner preference in males, but not in female rats. We discuss the implications for same-sex partner preferences.
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Przybyla JA, Cueva JP, Chemel BR, Joseph Hsu K, Riese DJ, McCorvy JD, Chester JA, Nichols DE, Watts VJ. Comparison of the enantiomers of (+/-)-doxanthrine, a high efficacy full dopamine D(1) receptor agonist, and a reversal of enantioselectivity at D(1) versus alpha(2C) adrenergic receptors. Eur Neuropsychopharmacol 2009; 19:138-46. [PMID: 19028082 PMCID: PMC2636714 DOI: 10.1016/j.euroneuro.2008.10.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/18/2008] [Revised: 09/17/2008] [Accepted: 10/21/2008] [Indexed: 11/20/2022]
Abstract
Parkinson's disease is a neurodegenerative condition involving the death of dopaminergic neurons in the substantia nigra. Dopamine D(1) receptor agonists are potential alternative treatments to current therapies that employ L-DOPA, a dopamine precursor. We evaluated the pharmacological profiles of the enantiomers of a novel dopamine D(1) receptor full agonist, doxanthrine (DOX) at D(1) and alpha(2C) adrenergic receptors. (+)-DOX displayed greater potency and intrinsic activity than (-)-DOX in porcine striatal tissue and in a heterologous D(1) receptor expression system. Studies in MCF7 cells, which express an endogenous human dopamine D(1)-like receptor, revealed that (-)-DOX was a weak partial agonist/antagonist that reduced the functional activity of (+)-DOX and dopamine. (-)-DOX had 10-fold greater potency than (+)-DOX at alpha(2C) adrenergic receptors, with an EC50 value of 4 nM. These findings demonstrate a reversed stereoselectivity for the enantiomers of DOX at D(1) and alpha(2C) receptors and have implications for the therapeutic utility of doxanthrine.
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Affiliation(s)
- Julie A. Przybyla
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN 47907
| | - Juan P. Cueva
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN 47907
| | - Benjamin R. Chemel
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN 47907
| | - K. Joseph Hsu
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN 47907
| | - David J. Riese
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN 47907
| | - John D. McCorvy
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN 47907
| | - Julia A. Chester
- Department of Psychological Sciences, Purdue University, West Lafayette, IN 47907
| | - David E. Nichols
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN 47907
| | - Val J. Watts
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN 47907
- Corresponding author, Purdue University, Dept. of Medicinal Chemistry and Molecular Pharmacology, 575 Stadium Mall Dr., RHPH 210, West Lafayette, IN 47907-2091, Tel. 765-469-3872, Fax. (765) 494-1414,
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Pian JP, Criado JR, Ehlers CL. Differential effects of acute alcohol on prepulse inhibition and event-related potentials in adolescent and adult Wistar rats. Alcohol Clin Exp Res 2008; 32:2062-73. [PMID: 18828807 DOI: 10.1111/j.1530-0277.2008.00794.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
BACKGROUND Previous studies have demonstrated that adolescent and adult rats show differential sensitivity to many of the acute effects of alcohol. We recently reported evidence of developmental differences in the effects of acute alcohol on the cortical electroencephalogram. However, it is unclear whether developmental differences are also observed in other neurophysiological and neurobehavioral measurements known to be sensitive to alcohol exposure. The present study determined the age-related effects of acute alcohol on behavioral and event-related potential (ERP) responses to acoustic startle (AS) and prepulse inhibition (PPI). METHODS Male adolescent and adult Wistar rats were implanted with cortical recording electrodes. The effects of acute alcohol (0.0, 0.75, and 1.5 g/kg) on behavioral and ERP responses to AS and PPI were assessed. RESULTS Acute alcohol (0.75 and 1.5 g/kg) significantly reduced the behavioral and electrophysiological response to AS in adolescent and adult rats. Both 0.75 and 1.5 g/kg alcohol significantly enhanced the behavioral response to PPI in adolescent, but not in adult rats. During prepulse + pulse trials, 1.5 g/kg alcohol significantly increased the N10 pulse response in the adolescent frontal cortex. Acute alcohol (0.75 and 1.5 g/kg) also increased the N1 ERP pulse response to prepulse stimuli in frontal and parietal cortices in adult rats, but not in adolescent rats. CONCLUSIONS These data suggest that alcohol's effect on behavioral and electrophysiological indices of AS do not differ between adults and adolescents whereas developmental stage does appear to significantly modify alcohol-influenced response to PPI.
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Affiliation(s)
- Jerry P Pian
- Scripps Research Institute, Department of Molecular and Integrative Neurosciences, La Jolla, California 92037, USA
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Sasaki H, Hanamoto A. Shock sensitization and fear potentiation of auditory startle response in hamsters. Percept Mot Skills 2008; 105:862-71. [PMID: 18229540 DOI: 10.2466/pms.105.3.862-871] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
It is well known that an auditory startle response can be modulated by several processes. In the present study shock sensitization and fear potentiation were examined in 17 hamsters to assess whether response enhancement is similar for another rodent. Immediately after presentation of electrical foot shocks, the auditory startle response increased significantly. This response was also enhanced after fear conditioning in the Experimental group using a light as a conditioned stimulus (CS) and the foot shock as the unconditioned stimulus (US). The auditory startle response remained unchanged in the Control group after nonpaired presentation of CS and US. Significant correlation between enhancement of the auditory startle response in sensitization and fear conditioning was found for the Experimental group. Shock sensitivity and effect of fear on modulation of the auditory startle response in hamsters are similar to those of other rodents. Further, neural mechanisms underlying enhancement of the auditory startle response seem not to be responsible for the deficit of prepulse inhibition in hamsters.
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Affiliation(s)
- Hitoshi Sasaki
- Department of Physiology and Biosignaling (A5), Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita 565-0871, Japan.
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SASAKI HITOSHI. SHOCK SENSITIZATION AND FEAR POTENTIATION OF AUDITORY STARTLE RESPONSE IN HAMSTERS. Percept Mot Skills 2007. [DOI: 10.2466/pms.105.7.862-871] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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