Inhibitory effect of cyclooxygenase inhibitors on the step-through passive avoidance performance in mice treated with NC-1900, an arginine-vasopressin fragment analog.
To examine the participation of endogenous cyclooxygenase (COX) in the mnemonic effect of NC-1900, an arginine-vasopressin fragment analog, the latencies of mice in the step-through passive avoidance (PA) task were determined following the administration of COX inhibitors and/or NC-1900 (1 ng/kg). When administered immediately after the acquisition trial (Acq) in the PA task, indomethacin (20 mg/kg), a nonspecific COX inhibitor, and NS-398 (10 and 20 mg/kg), a specific COX-2 inhibitor, but not piroxicam (10 and 20 mg/kg), a specific COX-1 inhibitor, decreased the latency on the retention trial (Ret). The mnemonic effect of 1 ng/kg NC-1900 on the Ret in the PA task was also inhibited by the administration of either indomethacin (20 mg/kg) or NS-398 (20 mg/kg) but not by piroxicam. However, when 20 mg/kg indomethacin and NS-398 were administered 3 h after the Acq, the increase in Ret latency induced by NC-1900 was not inhibited. These results suggested that the action of NC-1900 on the early stage of memory formation in the PA task may be modulated by endogenous COX-2 but not by COX-1.
Ishida
T
T
Department of Applied Pharmacology, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan.
Sato
T
T
Irifune
M
M
Tanaka
K
K
Hirate
K
K
Nakamura
N
N
Nishikawa
T
T
D000818:Animals; D001127:Arginine Vasopressin / Q000031:analogs & derivatives / Q000502:physiology; D001362:Avoidance Learning / Q000187:drug effects*; D001522:Behavior, Animal / Q000187:drug effects; D051546:Cyclooxygenase 2 / Q000378:metabolism; D016861:Cyclooxygenase Inhibitors / Q000494:pharmacology*; D007213:Indomethacin / Q000494:pharmacology*; D008297:Male; D008568:Memory / Q000187:drug effects; D051379:Mice; D008815:Mice, Inbred Strains; D009578:Nitrobenzenes / Q000494:pharmacology*; D009842:Oligopeptides / Q000494:pharmacology*; D010894:Piroxicam / Q000494:pharmacology*; D011761:Pyrrolidonecarboxylic Acid / Q000031:analogs & derivatives* / Q000494:pharmacology; D013449:Sulfonamides / Q000494:pharmacology*