SEX-DIFFERENCES IN THE ACTIVITY OF GAMMA-AMINOBUTYRIC ACIDERGIC NEURONS IN THE RAT HYPOTHALAMUS

The rate of GABA turnover was determined in nine microdissected brain regions in adult male and female rats. In the medial preoptic nucleus (central aspect) and ventromedial nucleus (ventrolateral aspect) of th e hypothalamus, areas involved in the regulation of gonadotropin secre tion and sex behavior, GABAergic neuronal activity was about 2-fold gr eater in males than females. These results demonstrate a striking sexu al dimorphism in the activity of specific populations of hypothalamic CABAergic neurons. (C) 1997 Elsevier Science B.V.