Hypothermic response produced by manassantin A, a novel neuroleptic agent.

Manassantin A (MNS-A), a novel neolignoid, neutral compound shown to possess neuroleptic properties, causes hypothermic response in male and female mice of CD-1 strain when administered by the intra-cerebroventricular (icv), (0.1, 1.0, 3.2, 10 micrograms/mouse), intraperitoneal (ip), (0.1, 0.32, 1.0, 3.2 mg/kg) and oral (0.5, 1.6, 5.0, 16 mg/kg) routes. The hypothermia was found to be dose and time dependent, the maximum decrease of temperature being observed by the icv route (P less than 0.001) after 2 hours. However, ip and oral administration of lower and middle order doses were not very effective but higher doses caused significant (P less than 0.001) reduction of body temperature. The centrally-induced hypothermic response by MNS-A may give future leads as a screening model for antidepressant drugs and can be a useful tool for manipulating physiological and pharmacological processes to understand the central thermoregulatory functions.