Amnesia Research Today is a free monthly online journal that collates and summarizes the latest research about Amnesia, including details on memory loss, causes, treatment, brain injury,.

Effect of NC-1900, an active fragment analog of arginine vasopressin, and inhibitors of arachidonic acid metabolism on performance of a passive avoidance task in mice.

Sato T, Ishida T, Irifune M, Tanaka K, Hirate K, Nakamura N, Nishikawa T

Department of Applied Pharmacology, Kagoshima University Graduate School of Medical and Dental Sciences, Sakuragaoka-8, Kagoshima 890-8544, Japan. tomsato@dentb.hal.kagoshima-u.ac.jp

In this study, we investigated the effect of administration of inhibitors of each of the arachidonic acid metabolism pathways and the effect of co-administration of these inhibitors with NC-1900, a fragment analog of arginine vasopressin, on step-through passive avoidance task performance. All drugs were administered just after the acquisition trial in the passive avoidance task. Intracerebroventricular (i.c.v.) administration of nordihydroguaiaretic acid (NDGA, 1 and 10 microg), a phospholipase A2 (PLA2) and lipoxygenase (LOX) inhibitor, and of arachidonyl trifluoromethyl ketone (ATK, 1 and 10 microg), a specific PLA2 inhibitor caused reductions in latency on the retention trial. The i.c.v. administration of either of baicalein (0.1-10 microg), a 12-LOX inhibitor, or AA-861 (0.1-10 microg), a 5-LOX inhibitor, did not influence the latency. Intraperitoneal administration of indomethacin (20 mg/kg), a non-specific COX inhibitor, or NS-398 (10 mg/kg), a specific COX-2 inhibitor, impaired performance on the retention trial in the task, while piroxicam (20 mg/kg), a specific COX-1 inhibitor, did not. Subcutaneous administration of NC-1900 (0.1 ng/kg) ameliorated the reduction of latency caused by NDGA, ATK, indomethacin, or NS-398. These results suggested that the COX-2 pathway of arachidonic acid metabolism may be important for learning and/or memory in the passive avoidance task in mice, and that the ameliorating effect of NC-1900, in part, is due to mimicking of the effects of metabolites of the COX-2 pathway.

Published 5 March 2007 in Eur J Pharmacol, 560(1): 36-41.
Full-text of this article is available online (may require subscription).

© 2004-2008 Amnesia Research Today. All Rights Reserved.