[Effect of epidermal growth factor (EGF) on mouse sperm capacitation].
The effect of epidermal growth factor (EGF) on the kinetics of mouse sperm capacitation was examined. The chlortetracycline (CTC) fluorescence assay was used to monitor capacitated sperm, featuring a B pattern. One hundred ng/ml EGF significantly stimulated capacitation at 15 minutes after the addition. However, 0.1 pg/ml EGF did not stimulate capacitation. EGF affected neither the motility nor the appearance of the S or AR pattern. The EGF-induced stimulation of capacitation was attenuated by 20 micrograms/ml genistein, an inhibitor of protein tyrosine kinase, or by 100 ng/ml thapsigargin, a non-phorbol tumor promoter, which inhibits EGF action by enhancing phosphorylation of the threonine 669 residue of the EGF-receptor. However, 3 ng/ml 12-O-tetradecanoly phorbol 13-acetate (TPA), a stimulator of protein kinase C, did not attenuate the appearance of the B pattern enhanced by 100 ng/ml EGF. These data suggest that EGF stimulates mouse sperm capacitation by activating the tyrosine kinase of the EGF-receptor which is regulated by multisite phosphorylation.
Furuya
S
S
Department of Obstetrics and Gynecology, Nerima General Hospital, Tokyo.
Endo
Y
Y
Oba
M
M
Ito
T
T
Suzuki
S
S
Nozawa
S
S
D000818:Animals; D004305:Dose-Response Relationship, Drug; D004815:Epidermal Growth Factor / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D066246:ErbB Receptors / Q000378:metabolism; D019833:Genistein; D007529:Isoflavones / Q000494:pharmacology; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D010766:Phosphorylation / Q000187:drug effects; D011505:Protein-Tyrosine Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism; D013075:Sperm Capacitation / Q000187:drug effects*; D013268:Stimulation, Chemical; D013729:Terpenes / Q000494:pharmacology; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D019284:Thapsigargin
D007529:Isoflavones; D013729:Terpenes; D004815:Epidermal Growth Factor; D019284:Thapsigargin; D019833:Genistein; D066246:ErbB Receptors; D011505:Protein-Tyrosine Kinases; D013755:Tetradecanoylphorbol Acetate