[Effect of somatostatin on neurons of partially deafferented amygdala in the rabbit]

Responses of 291 neurons to microelectrophoretically injected somatostatin were studied in the amygdala of rabbits under nembutal anesthesia. Both excitatory and inhibitory effects were found in contrast to earlier data on the only inhibitory reactions in hypothalamic neurons. After partial chronical deafferentation of the amygdala responses to somatostatin application were observed in 76% of the registered neurons, 90% of these neurons with background discharge frequency from 6 to 20 imp/s, responded by an increase in their activity, while inhibitory reactions were recorded in neurons with average background discharge frequency above 20 imp/s. Since amygdaloid neurons exert a regulating effect on the secretion of the growth hormone through somatostatin, it is suggested that the observed responses reflect one of their feedback mechanisms.