Short-term effects of intrahypothalamic colchicine.

Colchicine was injected in the vicinity of the medial forebrain bundle to cause an accumulation of catecholamines in the lateral hypothalamus proximal to the injection site. Such injections caused severe deficits in consummatory behavior and motor performance within a few hours after injection, which were accompanied by the accumulation of catecholamines in the hypothalamus. Behavioural deficits occurring within 24 h after colchicine injection cannot be attributed to reduced synaptic transmission in the striatum or to dopamine depletion because these events do not commence until 24-48 h after colchicine administration. This study demonstrates the importance of considering all neurochemical changes which accompany catecholamine depletion when assessing the role of the catecholamine-containing system in the regulation of behaviour.