The female steroid hormone progesterone regulates ovulation and supports pregnancy, but also controls human sperm function within the female reproductive tract. Progesterone causes elevation of sperm intracellular Ca(2+) leading to sperm hyperactivation, acrosome reaction, and perhaps chemotaxis toward the egg. Although it has been suggested that progesterone-dependent Ca(2+) influx into human ...

PURPOSE The aim of this work was to evaluate nuclear histone acetylation level and total histone acetyltransferase (HAT) and deacetylase (HDAC) activity in ejaculated sperm and their relevance to conventional sperm parameters. MATERIALS AND METHODS Thirty-three normozoospermic men were included in this study. Semen samples were processed by swim-up and then immunostained by six acetylation an...

In most species examined to date, spermatozoa mature during transit through the epididymis to become functionally competent to swim progressively, fertilize oocytes, and produce viable offspring. In the studies presented here, the status of spermatozoa obtained from the regions of the epididymis of the cynomolgus monkey (Macaca fascicularis) was examined. Epididymal fluid was collected by micro...

We previously identified 62, 39, 27 and 7 kDa porcine sperm plasma membrane proteins that demonstrated a predominant affinity for the porcine oocyte plasma membrane by Western ligand blotting. The current experiments were designed to further investigate the potential roles of these molecules in sperm-oocyte plasma membrane interaction. Abilities of these proteins to bind to the oocyte plasma me...

Aldosterone seems to play a role in the regulation of the electrolyte content of sperm and in the motility of spermatozoa. The aim of the study was to evaluate the presence of the mineralocorticoid receptor (MR) in human ejaculated spermatozoa. We have assayed MR on spermatozoa of freshly ejaculated sperm from healthy donors. The identification of MR was made by using immunohistochemistry and i...

OBJECTIVE We investigated the activation of caspases 8, 9, 1, and 3 in human ejaculated spermatozoa to study main pathways of apoptosis. Potential functional impact of this phenomenon and possible activation mechanisms were examined by [1] subjecting cells to freezing and thawing, and [2] testing the dependence of caspase activity on membrane integrity. DESIGN Experimental study. SETTING An...

BACKGROUND We examined the presence and function of tachykinins and the tachykinin-degrading enzymes neprilysin (NEP) and neprilysin-2 (NEP2) in human spermatozoa. METHODS Freshly ejaculated semen was collected from forty-eight normozoospermic human donors. We analyzed the expression of substance P, neurokinin A, neurokinin B, hemokinin-1, NEP and NEP2 in sperm cells by reverse-transcriptase ...

background: globozoospermia is a severe form of teratozoospermia (incidence < 0.1%) in infertile men that is characterized by round headed sperm and acrosomeless in semen. objective: to compare the semen parameters, protamine deficiency, and apoptosis in ejaculated spermatozoa between globozoospermic and normozoospermic men. materials and methods: thirty six semen samples were divided into two ...