Ultrastructural immunolocalization of leptin receptor in mouse brain

Antibodies directed to amino acids 877-894 (M-18) and 32-51 (K-20) were use d to localize leptin receptor by immunocytochemistry in mouse brain. Both a ntibodies stained several hypothalamic nuclei (paraventricular nucleus, sup raoptic nucleus, supraoptic retrochiasmatic nucleus, suprachiasmatic nucleu s, preoptic area, ventromedial nucleus, dorsomedial nucleus, lateral hypoth alamus, arcuate nucleus, ventral and dorsal premammillary nuclei), the thal amic and amygdaloid nuclei, neurons of the neocortex and archicortex and th e epithelial cells of the choroid plexus. While M-18 staining was concentra ted in the Golgi area, with K-20 it was dispersed in the cytoplasm. Glial c ells were stained only by K-20. These results suggest that the trans-membra ne forms of the receptor are concentrated at the membrane level of the Golg i complex of neurons and in epithelial cells of the choroid plexus while th e soluble form is dispersed in their cytoplasm. Glial cells express only th e soluble form.