ANTIEMETIC INHIBITS CONDITIONED TASTE-AVERSION, BUT NOT THE HYPOPHAGIA INDUCED BY EPINEPHRINE

It has been shown that relatively high doses of epinephrine (E) inject ed intraperitoneally (IF) produce hypophagia and conditioned taste ave rsion (CTA) in rats. We examined the possibility that E effects involv e malaise. For this purpose, changes in saccharin preference induced b y E injected IP (100 mu g/ kg) were determined after a previous admini stration of trimethobenzamide (TMB, 5 mg/kg), an antiemetic agent. E a lone decreased saccharin preference by 54% (p < 0.01), but only by 16% (not significant) in the presence of TMB. In contrast, the injection of 75 or 100 mu g/kg E reduced food intake by 50 and 85%, respectively (p < 0.01), regardless of previous injection of TMB. In conclusion, t he results suggest that E-induced malaise is not the direct cause of t he hypophagia it elicits. (C) 1997 Elsevier Science Inc.