[Participation of beta-endorphins in organizing neuronal activity of the rabbit hypothalamic "hunger centers"].

Microiontophoretic application of beta-endorphin activated neuronal activity (48%) rather than inhibited it (38%) or had no effect whatsoever (14%) in the later hypothalamus of satiated rabbits. Naloxone inhibited the neuronal activity in 75% of the cases as well as activated it (25%), no areactive neurons having been found. The variations of latency of the interspike intervals due to the effect of beta-endorphin depended on the background activity of the neurons. The beta-endorphin--sensitive neurons seem to play a part both in neuronal mechanisms of feeding motivation and in those of satiation.