Environmental changes modify the expression of Diazepam

MARIELA F. PÉREZ.; MAGLIO LE; GERARDO R MARCHESINI; MOLINA JC; OSCAR A RAMIREZ

BEHAVIOURAL BRAIN RESEARCH

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2002 vol. 136 p. 75 - 75

0166-4328

arly results from our laboratory have demonstrated a positive correlation between increased hippocampal synaptic plasticity and development of tolerance to hypolocomotive effect of Diazepam (DZ). We have found recently, that pre-exposure to DZ administration context impairs increase of hippocampal synaptic plasticity in conjunction with tolerance to DZ. These findings have suggested, that the tolerance to DZ is context specific. Furthermore, the hippocampus can be critically involved in the behavioral expression of conditioned tolerance to DZ. The results of the present investigation show that animals chronically treated with DZ for 18 days exhibit withdrawal signs, evaluated as an increased anxiety in an elevated plus maze. These animals also show, a facilitation in the threshold to induce long-term potentiation in the hippocampal formation. These phenomena have a strong dependency on the drug administration context, since both are reversed after the introduction of some changes in t