LEPTIN RECEPTORS IN ESTROGEN RECEPTOR-CONTAINING NEURONS OF THE FEMALE RAT HYPOTHALAMUS

This study was undertaken to reveal whether integration of the periphe ral signals, leptin and estradiol, that convey information on the meta bolic state and gonadal function, respectively, might occur in the sam e hypothalamic neuronal perikarya. Light and electron microscopic immu nolabeling for leptin receptors (LRs) and estrogen receptors (ERs) was carried out on hypothalamic sections of female rats. In the medial pr eoptic area, periventricular regions, including the parvicellular para ventricular nucleus, the arcuate nucleus and the ventromedial hypothal amic nucleus, all of the cells that expressed immunoreactivity for ERs were also immunopositive for LR. On the other hand, only a subpopulat ion of LR-containing cells was found to express ERs. The extensive col ocalization of receptors for leptin and estrogen in neuronal perikarya of all parts of the hypothalamus suggests a closely coupled interacti on between these peripheral signals in the regulation of a variety of behavioral and neuroendocrine mechanisms. (C) 1998 Elsevier Science B. V. All rights reserved.