Endocrinology, Vol 114, 2284-2292, Copyright © 1984 by Endocrine Society

ARTICLES

Interaction of angiotensin II with dispersed cells from the anterior pituitary of the male rat

S Paglin, H Stukenbrok and JD Jamieson

Membranes from 6-week-old male rat anterior pituitaries possess saturable binding sites for angiotensin II (AII; Kd = approximately 2 X 10(-9) M). The binding is specific since it can be competed for with [Sar1,Leu8]AII and is unaffected by the presence of insulin or cholecystokinin octapeptide at nanomolar concentrations. To find out which cell types specifically interact with AII, rat anterior pituitaries were enzymatically dispersed and exposed to [125]iodo-AII (2 nM) in the absence or presence of [Sar1,Leu8]AII (400 nM). The cells were then washed free of unbound ligand and processed for light and electron microscopic autoradiography. Distribution of autoradiographic grains revealed that three cell types were specifically labeled with [125I]iodo-AII, namely mammotrophs, corticotrophs, and presumptive thyrotrophs. These cells were all labeled in the presence of [125I]iodo- AII alone (experimentals), whereas only 10-30% of them were labeled when 400 nM [Sar1,Leu8]AII was included in the binding reaction (controls). The number of grains over the labeled cells in the controls was 20% of that found in the experimental cells. These results may imply that AII can regulate anterior pituitary functions under physiological conditions by interacting directly with its secretory cells.

This article has been cited by other articles:

				E. Vila–Porcile, A. Barret, and P. Corvol Secretion of Renin-Angiotensin System (RAS) Components by Normal and Tumoral Lactotropes: A Comparative Study Using Reverse Hemolytic Plaque Assay (RHPA) and Immunoelectron Microscopy J. Histochem. Cytochem., December 1, 2000; 48(12): 1691 - 1704. [Abstract] [Full Text]

				M. E. Freeman, B. Kanyicska, A. Lerant, and G. Nagy Prolactin: Structure, Function, and Regulation of Secretion Physiol Rev, October 1, 2000; 80(4): 1523 - 1631. [Abstract] [Full Text] [PDF]

				Z. Lenkei, A. M. Nuyt, D. Grouselle, P. Corvol, and C. Llorens-Cortès Identification of Endocrine Cell Populations Expressing the AT1B Subtype of Angiotensin II Receptors in the Anterior Pituitary Endocrinology, January 1, 1999; 140(1): 472 - 477. [Abstract] [Full Text]

				O. Johren, G. L. Sanvitto, G. Egidy, and J. M. Saavedra Angiotensin II AT1A Receptor mRNA Expression Is Induced by Estrogen-Progesterone in Dopaminergic Neurons of the Female Rat Arcuate Nucleus J. Neurosci., November 1, 1997; 17(21): 8283 - 8292. [Abstract] [Full Text] [PDF]