This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Mededovic, S. Articles by Fraser, L. R Search for Related Content PubMed PubMed Citation Articles by Mededovic, S. Articles by Fraser, L. R

Angiotensin II stimulates cAMP production and protein tyrosine phosphorylation in mouse spermatozoa

Centre for Reproduction, Endocrinology and Diabetes, School of Biomedical Sciences, King’s College London, Guy’s Campus, London Bridge, London SE1 1UL, UK

Correspondence should be addressed to L R Fraser; Email: lynn.fraser{at}kcl.ac.uk

Angiotensin II (AII), found in seminal plasma, has been shown to stimulate capacitation in uncapacitated mammalian spermatozoa. The present study investigated the location of AII receptors on spermatozoa and AII’s mechanism of action. AT1 type receptors for AII are present on the acrosomal cap region and along the whole of the flagellum of both mouse and human spermatozoa. Because combinations of low concentrations of AII and either calcitonin or fertilization-promoting peptide (FPP), both known to regulate the adenylyl cyclase (AC)/cAMP signal transduction pathway, elicited a significant response, this study investigated the hypothesis that these peptides act on the same pathway. AII was shown to significantly stimulate cAMP production in both uncapacitated and capacitated mouse spermatozoa and this was associated with increases in protein tyrosine phosphorylation. Using an anti-phosphotyrosine antibody to visualize the location of tyrosine phosphoproteins within individual cells, AII significantly stimulated phosphorylation within 20 min in both the head, especially in the acrosomal cap region, and the flagellum, especially in the principal piece, of uncapacitated mouse spermatozoa; combined AII + FPP was stimulatory within 5 min. In addition, Western blotting revealed that AII stimulation increased phosphorylation in a number of tyrosine phosphoproteins in both uncapacitated and capacitated mouse spermatozoa, with some being altered only in the latter category of cells. These results support the hypothesis that AII stimulates AC/cAMP in mammalian spermatozoa.

This article has been cited by other articles:

				S.A. Adeoya-Osiguwa and L. R. Fraser Cathine, an amphetamine-related compound, acts on mammalian spermatozoa via beta1- and {alpha}2A-adrenergic receptors in a capacitation state-dependent manner Hum. Reprod., March 1, 2007; 22(3): 756 - 765. [Abstract] [Full Text] [PDF]

				S. Mededovic and L. R Fraser Mechanisms of action of angiotensin II on mammalian sperm function Reproduction, February 1, 2005; 129(2): 211 - 218. [Abstract] [Full Text] [PDF]