Activation of GABA(B) receptors reverses spontaneous gating deficits in juvenile DBA/2J mice

作者:Bortolato Marco*; Frau Roberto; Orru Marco; Piras A Paola; Fa Mauro; Tuveri Antonella; Puligheddu Monica; Gessa Gian Luigi; Castelli M Paola; Mereu Giampaolo; Marrosu Francesco
来源:Psychopharmacology, 2007, 194(3): 361-369.
DOI:10.1007/s00213-007-0845-5

摘要

Rationale Gamma-amino-butyric acid (GABA)(B) receptors play a key role in the pathophysiology of psychotic disorders. We previously reported that baclofen, the prototypical GABA(B) agonist, elicits antipsychotic-like effects in the rat paradigm of prepulse inhibition (PPI) of the startle, a highly validated animal model of schizophrenia.
Objectives We studied the role of GABA(B) receptors in the spontaneous PPI deficits displayed by DBA/2J mice.
Materials and methods We tested the effects of baclofen (1.25-5 mg/kg, intraperitoneal [i.p.]) in DBA/2J and C57BL/6J mice, in comparison to the antipsychotic drugs haloperidol (1 mg/kg, i.p.) and clozapine (5 mg/kg, i.p.). Furthermore, we investigated the expression of GABA(B) receptors in the brain of DBA/2J and C57BL/6J mice by quantitative autoradiography.
Results Baclofen dose-dependently restored PPI deficit in DBA/2J mice, in a fashion similar to the antipsychotic clozapine (5 mg/kg, i.p.). This effect was reversed by pretreatment with the GABA(B) antagonist SCH50211 (50 mg/kg, i.p.). In contrast, baclofen did not affect PPI in C57BL/6J mice. Finally, quantitative autoradiographic analyses assessed a lower GABA(B) receptor expression in DBA/2J mice in comparison to C57BL/6J controls in the prefrontal cortex and hippocampus but not in other brain regions.
Conclusions Our data highlight GABA(B) receptors as an important substrate for sensorimotor gating control in DBA/2J mice and encourage further investigations on the role of GABA(B) receptors in sensorimotor gating, as well as in the pathophysiology of psychotic disturbances.

  • 出版日期2007-10