Chloride efflux during the progesterone-initiated human sperm acrosome reaction is inhibited by lavendustin A, a tyrosine kinase inhibitor

• Published in: Journal of andrology Vol. 17; no. 4; pp. 327 - 330
• Main Authors: Meizel, S, Turner, K. O
• Format: Journal Article
• Language: English
• Published: San Fransisco, CA Am Soc Andrology 01.07.1996; American Society of Andrology
• Subjects: Acrosome - drug effects; Acrosome - physiology; Biological and medical sciences; Chloride Channels - physiology; Enzyme Inhibitors - pharmacology; Fluorescent Dyes; Fundamental and applied biological sciences. Psychology; Hormone metabolism and regulation; Humans; Male; Mammalian male genital system; Phenols - pharmacology; Progesterone - pharmacology; Protein-Tyrosine Kinases - antagonists & inhibitors; Vertebrates: reproduction; Human; Spermatozoa; Enzyme; Transferases; Enzyme inhibitor; Ion transport; Male; Acrosome reaction; Ionic channel; Germinal cell; Fecundation; Ovarian hormone; Reproduction; Chlorides; Inhibition; Progesterone; Sex steroid hormone; Mechanism of action; Protein-tyrosine kinase
• ISSN: 0196-3635; 1939-4640

Previous studies showed that progesterone (P) can initiate the mammalian sperm acrosome reaction (AR) in vitro and that a sperm GABAA-like receptor/Cl- channel is involved in an essential Cl- efflux mediated by P during the AR. Here, we show that lavendustin A, a potent, specific inhibitor of tyrosine kinase activity, strongly inhibits the P-initiated human AR and the essential P-mediated Cl- efflux. Lavendustin B, a weak tyrosine kinase inhibitor, had no significant effect. These results suggest that, as part of AR initiation, P mediates tyrosine phosphorylation of the sperm GABAA- like receptor/Cl- channel.