WATER-DEPRIVATION UP-REGULATES ANG-II AT(1) BINDING AND MESSENGER-RNAIN RAT SUBFORNICAL ORGAN AND ANTERIOR-PITUITARY

Citation
Gl. Sanvitto et al., WATER-DEPRIVATION UP-REGULATES ANG-II AT(1) BINDING AND MESSENGER-RNAIN RAT SUBFORNICAL ORGAN AND ANTERIOR-PITUITARY, American journal of physiology: endocrinology and metabolism, 36(1), 1997, pp. 156-163
Citations number
35
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Physiology
ISSN journal
0193-1849
Volume
36
Issue
1
Year of publication
1997
Pages
156 - 163
Database
ISI
SICI code
0193-1849(1997)36:1<156:WUAABA>2.0.ZU;2-9
Abstract
We studied angiotensin Il (ANG II) receptor subtype expression in sele cted brain nuclei and pituitary gland after water deprivation by in vi tro receptor autoradiography using I-125-labeled [Sar(1)]ANG II and by in situ hybridization using S-35-labeled AT(1A), AT(1B), and AT(2) re ceptor-specific riboprobes. In control rats we found binding to AT(1) receptors in the subfornical organ, paraventricular nucleus. median em inence, and anterior pituitary; AT(1A) mRNA expression in the subforni cal organ and paraventricular nucleus; and AT(1B) mRNA expression in t he anterior pituitary. No receptor mRNA was found in the median eminen ce. AT(1) receptors and AT(1A) receptor mRNA levels were increased in the subfornical organ, and, in the anterior pituitary, AT(1) receptors and AT(1B) receptor mRNA were increased, only after 5 days of water d eprivation. No significant changes occurred after 1 or 3 days of water deprivation, and no regulation of ANG II receptor expression was dete cted in other brain areas. Our results show that prolonged water depri vation selectively regulates AT(1) receptor expression and AT(1A) and AT(1B) receptor mRNA levels in the subfornical organ and anterior pitu itary, respectively, supporting a role for these receptors during sust ained dehydration.