St john's wort (Hypericum perforatum) counteracts deleterious effects of the chronic restraint stress on recall in rats.
This study aimed at verifying a hypothesis that St. John's wort (Hypericum perforatum) alleviates stress-induced memory impairments. Administration of Hypericum perforatum (350 mg kg(-1) daily for 21 days) significantly enhanced recall of passive avoidance behavior (PAB), but had no effect on the acquisition of conditioned avoidance responses (CARs). Rats stressed chronically (2 h daily for 21 days) displayed diminished recall of the PAB and this effect was abolished by St John's wort. Chronic administration of the "equivalent" to the stress dose of exogenous corticosterone (5 mg kg(-1) daily for 21 days) also impaired recall of PAB, and this effect was also reversed by Hypericum perforatum. None of our treatments produced significant motor coordination impairments as tested in a 'chimney' test. It appears that H. perforatum prevents stress-induced deterioration of memory in rats.
Trofimiuk
Emil
E
Department of Clinical Pharmacology, Medical University of Bialystok, Waszyngtona 15A, 15-274 Bialystok, Poland. e_trofim@amb.edu.pl.
Walesiuk
Anna
A
Braszko
Jan J
JJ
D000818:Animals; D000893:Anti-Inflammatory Agents / Q000494:pharmacology; D001362:Avoidance Learning / Q000187:drug effects; D002908:Chronic Disease; D003213:Conditioning, Psychological / Q000187:drug effects; D003345:Corticosterone / Q000494:pharmacology; D004195:Disease Models, Animal; D020902:Hypericum; D008297:Male; D011939:Mental Recall / Q000187:drug effects*; D009043:Motor Activity / Q000187:drug effects; D008517:Phytotherapy; D011208:Powders; D051381:Rats; D017208:Rats, Wistar; D012149:Restraint, Physical; D013312:Stress, Physiological / Q000188:drug therapy* / Q000209:etiology
D000893:Anti-Inflammatory Agents; D011208:Powders; D003345:Corticosterone