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Reproductive and Urinary Physiology Commons

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Life Sciences

Old Dominion University

Spermatozoa

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Full-Text Articles in Reproductive and Urinary Physiology

Map Kinases In Cynomolgus Monkey Sperm Hyperactivation, Emily Nicole Haynes Oct 2001

Map Kinases In Cynomolgus Monkey Sperm Hyperactivation, Emily Nicole Haynes

Biological Sciences Theses & Dissertations

Mammalian sperm exhibit characteristic motility patterns, termed hyperactivated (HA) motility, associated with completion of capacitation. In cynomolgus monkey (Macaca fascicularis) sperm, this HA motility is dependent in vitro upon the addition of exogenous cyclic nucleotide mediators, caffeine and dibutyryl-cyclic adenosine monophosphate (dbcAMP). Previous reports have shown protein tyrosine phosphorylation to be an integral component of this caffeine- and cAMP-stimulated HA motility. This study investigated the involvement of the mitogen-activated protein (MAP) kinase-signaling cascade. Semen specimens were collected in Talp-HEPES medium from proven breeders via electroejaculation. After washing, sperm were incubated in the presence and absence of the MAP …


Progesterone And 17 Α-Hydroxyprogesterone: Novel Stimulators Of Calcium Influx In Human Sperm, Peter F. Blackmore, Stephen J. Beebe, Douglas R. Danforth, Nancy Alexander Jan 1990

Progesterone And 17 Α-Hydroxyprogesterone: Novel Stimulators Of Calcium Influx In Human Sperm, Peter F. Blackmore, Stephen J. Beebe, Douglas R. Danforth, Nancy Alexander

Bioelectrics Publications

Progesterone and 17 alpha-hydroxyprogesterone (but not other steroids such as testosterone, corticosterone, beta-estradiol, estrone, dehydroepiandrosterone, 20 alpha-hydroxypregnen-3-one, androstenedione, and pregnenolone) were shown to cause an immediate increase, in free cytosolic calcium ([Ca2+]i) in both capacitated and noncapacitated human sperm, using the fluorescent indicator fura 2. Significant increases in [Ca2+]i were observed with 10 ng/ml progesterone, while maximum effects were seen with 1 microgram/ml progesterone. Two other steroids 11 beta-hydroxyprogesterone and 5 alpha-pregnane-3,20-dione exhibited significant activity to increase [Ca2+]i. This increase in [Ca2+]i elicited by progesterone was entirely due to Ca2+ influx from the extracellular medium since the increase in [Ca2+]i …