Protein kinase enzymes in the human vagina-relation to key mediators of the cyclic AMP and cyclic GMP pathways.

Aside from phosphodiesterase (PDE) isoenzymes, protein kinases (cAK=cyclic AMP-binding protein kinase, cGK=cyclic GMP-binding protein kinase) have also been identified as important receptors for cyclic nucleotides. A significance of protein kinases in the control of the function of the male and female reproductive tract has been suggested; however, up until today, only a few approaches have addressed these enzymes in female genital tissues. The present study aimed to investigate by means of biochemical and immunohistochemical methods the expression of cAK and cGK.

Effects of endopeptidase inhibition on the contraction-relaxation response of isolated human vaginal tissue.

INTRODUCTION.: Vasoactive peptides, such as bradykinin, C-type natriuretic peptide (CNP), vasoactive intestinal polypeptide (VIP), and endothelin 1 (ET-1), are assumed to be involved in the control of female genital vascular and nonvascular smooth muscle. Tissue levels of said peptides are controlled by the activity of endopeptidase enzymes.

Rho kinase-related proteins in human vaginal arteries: an immunohistochemical and functional study.

Introduction: The calcium-sensitizing Rho A/Rho kinase pathway has been suggested to play a role in the control of nongenital vascular smooth muscle. Rho-associated kinases (ROKs) cause calcium-independent modulation of smooth muscle contraction, and have been demonstrated in the bladder, prostate, and corpus cavernosum. Until now, it is not known whether ROKs and related proteins play a role in the control of vaginal blood flow.

Endogenous vasoactive peptides and the human vagina--a molecular biology and functional study.

Introduction: Endogenous peptides, such as vasoactive intestinal polypeptide (VIP), C-type natriuretic peptide (CNP), and bradykinin (BK), have been proposed to play a role in the female sexual arousal response by exerting relaxation of clitoral, labial, and vaginal smooth muscle. While the effects of endogenous peptides on the human male erectile tissue have already been described, only very few studies have been conducted to investigate the peptidergic control of female genital tissues, including the vagina.

Aims: To elucidate the expression of mRNA specifically encoding for peptide receptors in the human vagina and the effects of VIP, CNP, and BK on the tension induced by endothelin-1 (ET-1) of isolated human vaginal wall smooth muscle.

In vitro functional responses of isolated human vaginal tissue to selective phosphodiesterase inhibitors.

Only little is known as to the significance of the cyclic nucleotide-mediated signal transduction in the control of the function of human vaginal smooth musculature. Recently, the presence of the phosphodiesterase (PDE) isoenzymes 4 (cAMP-PDE) and 5 (cGMP-PDE) in the human vagina was reported. Thus, it was the aim of the study to elucidate the effects of some PDE inhibitors on the tension induced by endothelin 1 (ET-1), as well as on levels of cGMP and cAMP in isolated human vaginal wall tissue.