Preexposure to Drug Administration Context Blocks the Development of Tolerance to Sedative Effects of Diazepam

RAUL H. MARIN; MARIELA F. PÉREZ; DANTE G. DUERO; OSCAR A. RAMIREZ

PHARMACOLOGY BIOCHEMISTRY AND BEHAVIOR

Elsevier Science

Lugar: U.S.A.; Año: 1999 vol. 64 p. 473 - 473

0091-3057

span lang="en" style="FONT-SIZE: 12pt; FONT-FAMILY: "Times New Roman"; mso-fareast-font-family: "Times New Roman"; mso-ansi-language: EN-GB; mso-fareast-language: ES; mso-bidi-language: AR-SA">The development of tolerance to benzodiazepine (BDZ) and other psychoactive agents such as morphine, alcohol, and barbiturates is thought to be a contingent or learning phenomenon. In a previous report, we demonstrated a positive correlation between the development of tolerance to the sedative effects of diazepam (DZ) and hippocampal synaptic plasticity. The results of the present work show that the development of tolerance to the hypolocomotor action of DZ (5 mg/kg) for 4 days and the associated increase in synaptic plasticity are context specific. Because animal preexposure to the drug administration context blocks both the tolerance sedative effects of DZ and the increased hippocampal synaptic plasticity, observed after 4 days of DZ administration, we propose the increased