title: Lack of tolerance development to benzodiazepines in antagonism of the pentylenetetrazol discriminative stimulus.
abstract: In an operant procedure of lever pressing on FR 10 schedule of food reinforcement male hooded rats were trained to respond on a lever on one side of a food cup following a 20 mg/kg pentylenetetrazol (PTZ) injection and to respond on a lever on the alternate side following a 1 ml/kg saline injection. Upon acquisition of the PTZ-saline discrimination, diazepam and chlordiazepoxide were tested and found to antagonize the PTZ discriminative stimulus. The animals were then injected with 10 mg/kg diazepam or chlordiazepoxide for ten consecutive days. New dose-response curves obtained following this treatment indicated that tolerance did not develop to the antagonism of the PTZ discriminative stimulus by these benzodiazepines.
mesh_terms: D000818:Animals; D014151:Anti-Anxiety Agents / Q000494:pharmacology*; D002707:Chlordiazepoxide / Q000494:pharmacology; D003975:Diazepam / Q000494:pharmacology; D004192:Discrimination, Psychological / Q000187:drug effects*; D004361:Drug Tolerance; D008297:Male; D010433:Pentylenetetrazole / Q000037:antagonists & inhibitors*; D051381:Rats; D012055:Reinforcement Schedule
chemical_list: D014151:Anti-Anxiety Agents; D002707:Chlordiazepoxide; D003975:Diazepam; D010433:Pentylenetetrazole