Learning/memory processes under stress conditions.
Using mice, changes in the learning/memory processes under various stress conditions were investigated in one-trial step-through type passive avoidance learning task. Pre-, post-training and pre-test foot shock (FS)-stress induced long-lasting, at least 96 h, facilitation of test trial latencies. Pre-training psychological (PSY)-stress induces facilitation and pre-test swimming (SW)-stress provokes impairment of test trial latencies. These effects of FS-, PSY- and SW-stress are all dependent on the timing of their exposure and due to their acute effect. Intraperitoneal administration of 1 mg/kg scopolamine 30 min pre-training caused impairment of test latencies in naive and pre-test FS-stressed animals but failed to affect both pre- and post-training FS-induced enhancement. Taken all these data together, it seems that cholinergic mechanism is partly involved in the FS-stress induced facilitation of test latencies, though the research on the changes in ACh levels at the action site in brain after FS-stress exposure is necessary for a definite conclusion.
Kaneto
H
H
Department of Pharmacology, Faculty of Pharmaceutical Sciences, Nagasaki University, Japan.
D000818:Animals; D001362:Avoidance Learning / Q000187:drug effects; D018680:Cholinergic Antagonists / Q000008:administration & dosage / Q000494:pharmacology; D004597:Electroshock; D007274:Injections, Intraperitoneal; D007858:Learning / Q000502:physiology*; D008297:Male; D008568:Memory / Q000502:physiology*; D051379:Mice; D008815:Mice, Inbred Strains; D010275:Parasympathetic Nervous System / Q000502:physiology*; D012601:Scopolamine / Q000494:pharmacology; D013315:Stress, Psychological / Q000523:psychology*; D013997:Time Factors
D018680:Cholinergic Antagonists; D012601:Scopolamine