| Natriuretic peptides form a family of structurally-related peptides known to regulate salt and water homeostasis and to cause vasodilation. Synthesis of atrial (ANP), brain (BNP), and C-type (CNP) natriuretic peptides occurs mainly in the heart and brain and has been identified recently in the female reproductive tract. The expression of ANP and CNP, as well as their cognate guanylyl cyclase receptors (NPR-A and NPR-B, respectively), have been detected in the rat ovary.;We have shown previously that the expression of the natriuretic peptides and their receptors, in the rat ovary, is modulated by the estrous cycle. Since estrogen and the gonadotropins (luteinizing hormone (LH) and follicle-stimulating hormone (FSH)) are important regulators of follicular development and ovarian function we hypothesized that expression of the natriuretic peptide system is modulated by these hormones. In order to test this hypothesis, the expression of the natriuretic peptide system (peptide and receptor) was evaluated in ovarian cells (granulosa and residual tissue cells) obtained from immature female rats treated with either diethylstilbestrol (DES), an estrogen analogue, or equine chorionic gonadotropin (eCG), a gonadotropin which possesses both LH and FSH activity. (Abstract shortened by UMI.). |
