Atypical antipsychotic olanzapine reversed deficit on prepulse inhibition of the acoustic startle reflex produced by microinjection of dizocilpine (MK-801) into the inferior colliculus in rats

Author(s)

Zangrando, Julia ^[1] ; Carvalheira, Renata ^[1] ; Labbate, Giovanna ^[1] ; Medeiros, Priscila ^[1] ; Longo, Beatriz Monteiro ^[2] ; Melo-Thomas, Liana ^[1] ; Barbosa Silva, Regina Claudia ^[1]

Affiliation

^[1] Univ Fed Sao Paulo Unifesp, Dept Biociencias, Lab Psicol Expt, BR-11060001 Santos, SP - Brazil

^[2] Univ Fed Sao Paulo Unifesp, Dept Fisiol, Lab Neurofisiol, BR-04023066 Sao Paulo - Brazil

• Document type: Journal article
• Source: Behavioural Brain Research; v. 257, p. 77-82, NOV 15 2013.
• Web of Science Citations: 8

Abstract

Patients with schizophrenia exhibit deficits in an operational measure of sensorimotor gating: prepulse inhibition (PPI) of startle. PPI is the normal reduction in the startle response caused by a low intensity non-startling stimulus (prepulse) which is presented shortly before the startle stimulus (pulse). MK-801 is an NMDA receptor-antagonist known to produce hyperactivity, deficits in prepulse inhibition and social withdrawal, behaviors which correlate well with some of the positive, cognitive and negative symptoms of schizophrenia. The inferior colliculus (IC) is a critical part of the auditory pathway mediating acoustic PPI. The activation of the IC by the acoustic prepulse reduces startle magnitude. Thus, the purpose of the present study was to elucidate the role of glutamatergic transmission in the IC on the expression of acoustic PPI. For that we investigated whether NMDA receptor stimulation or blockade would affect this response. Unilateral microinjections of NMDA (30 nmol/0.5 mu L) into the IC did not alter PPI while microinjections of MK-801 (30 nmol/0.5 mu L) into this structure disrupted PPI. We also examined the ability of the atypical antipsychotic olanzapine (5.0 mg/kg; i.p.) to reverse the disruption of pre-pulse inhibition produced by unilateral microinjections of MK-801 into the IC of rats. Pretreatment with olanzapine blocked MK-801-induced disruption of PPI. Altogether, these results suggest that glutamate-mediated mechanisms of the IC are involved in the expression of PPI in rodents and that this response is sensitive to atypical antipsychotic olanzapine. (C) 2013 Elsevier B.V. All rights reserved. (AU)

• FAPESP's process: 12/01062-7 - Participation of the glutamatergic neurotransmission of the inferior colliculus in the modulation of prepulse inhibition of the acoustic startle reflex, motor behavior and social interaction in rats
• Grantee: Regina Cláudia Barbosa da Silva
• Support Opportunities: Regular Research Grants
• FAPESP's process: 11/01409-4 - Electrical stimulation and recording of the neural activity into the inferior colliculus during the haloperidol-induced catalepsy: a behavioral and electrophysiologic study
• Grantee: Liana Melo-Thomas
• Support Opportunities: Regular Research Grants
• FAPESP's process: 12/05021-3 - Participation of the glutamatergic neurotransmission of the inferior colliculus in the modulation of prepulse inhibition of the acoustic startle reflex, motor behavior and social interaction in rats
• Grantee: Júlia Flávia Zangrando
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• FAPESP's process: 10/14446-2 - Involvement of the glutamatergic neurotransmission in the inferior colliculus on the catalepsy induced by intraestriatal haloperidol microinjection
• Grantee: Priscila Medeiros de Freitas
• Support Opportunities: Scholarships in Brazil - Master
• FAPESP's process: 12/06275-9 - Participation of the glutamatergic neurotransmission of the inferior colliculus in the modulation of prepulse inhibition of the acoustic startle reflex, motor behavior and social interaction in rats
• Grantee: Renata Rodrigues Carvalheira
• Support Opportunities: Scholarships in Brazil - Scientific Initiation