Interaction of angiotensin II and III with adenosine A(1) receptor-related drugs in passive avoidance conditioning in rats.
The present study examines the functional interaction between angiotensins (ANG II and III) and adenosine A(1) receptor-related drugs on passive avoidance (step-through) conditioning in rats. ANG II and III were administered intracerebroventricularly (i.c.v.) while N(6)-cyclohexyladenosine (CHA) and theophylline-intraperitoneally (i.p.), immediately after the training trial. ANG II (0.1,0.5,1 microg) induced dose-dependent (inverted-U) increase of the retention while ANG III in the same doses decreased it upon re-testing of rats 24 h and 7 days later. The selective adenosine A(1) receptor agonist CHA (0.1 mg/kg) attenuated memory-enhancing effect of ANG II (0.1 microg) 24 h but not 7 days after the training session. Conversely, CHA had opposite i.e. facilitating effect on ANG III (0.1 microg) response upon re-testing 24 h and 7 days later. The pretreatment with ANG III attenuated the retention-improving effect exerted by the non-specific adenosine A(1)/A(2) receptor antagonist theophylline (75 mg/kg) 24 h and 7 days after the training trial. Taken together, the results show a mutual interaction of the drugs belonging to the adenosine and angiotensin modulatory systems in memory consolidation of rats.
Tchekalarova
J
J
Laboratory Experimental Psychopharmacology, Institute of Physiology, Bulgarian Academy of Sciences, Acad. G. Bonchev Str., Bl.23, 1113 Sofia, Bulgaria. jane_tch@yahoo.com
Kambourova
T
T
Georgiev
V
V
D000241:Adenosine / Q000031:analogs & derivatives* / Q000494:pharmacology; D000804:Angiotensin II / Q000494:pharmacology*; D000805:Angiotensin III / Q000494:pharmacology*; D000818:Animals; D001362:Avoidance Learning / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D007274:Injections, Intraperitoneal; D007276:Injections, Intraventricular; D008297:Male; D008568:Memory / Q000187:drug effects; D051381:Rats; D017208:Rats, Wistar; D018047:Receptors, Purinergic P1 / Q000187:drug effects*; D013806:Theophylline / Q000494:pharmacology
D018047:Receptors, Purinergic P1; D000804:Angiotensin II; D000805:Angiotensin III; C027513:N(6)-cyclohexyladenosine; D013806:Theophylline; D000241:Adenosine