Angiotensin II Receptor Development in the Bed Nucleus of the Stria terminalis and Other Perihypothalamic Brain Regions of the Female and Male Rat

Abstract

Brain angiotensin II (AII) receptors play a role in the regulation of luteinizing hormone release. This action is thought to involve luteinizing hormone-releasing hormone containing neurons in the preoptic-anterior hypothalamic (POAH) area of the brain. Previous studies have demonstrated a discrete locus of AII receptor binding sites and responsiveness within the POAH to microinjections of AII in the adult female rat, corresponding to the ventral portion of the bed nucleus of the stria terminalis (BSTV). To further characterize the age- and sex-dependent AII receptor binding in the BSTV and other brain regions, in vitro receptor autoradiography using ¹²⁵I-sarcosine¹, isoleucine⁸ AII (¹²⁵I-SI AII) was performed on 2-, 4- and 10-week-old female and male rat brains. Rats of both sexes displayed an age-dependent increase in ¹²⁵I-SI AII binding in the BSTV, as well as in the suprachiasmatic nucleus (SCh). There was no detectable difference in binding within the BSTV between the female and male of any age group. Prepubertal ovariectomy did not impair the expression of ¹²⁵I-SI AII binding in the BSTV or the SCh of adult female rats. The developmental expression of AII receptors in the BSTV and SCh may therefore play a role in sexual maturation and regulation of sexual function in the rat.

Pituitary lactotrope expresses transforming growth factor β (TGFβ) type II receptor mRNA and protein and contains 125I-TGFβ1 binding sites

“…Autoradiographic localization of ,25I-TGFßl binding sites in the pituitary tissues was carried out using previously published methods (Kuhar 1985, Grove et al 1992, Chigini et al 1994. Pituitaries from ovariectomized rats with or without estrogen treatment were obtained, quick frozen in cold isopentane ( -20°C ) and 10-12 pm sec¬ tions were cut in a cryostat.…”