A factor in human seminal plasma which affects carnitine accumulation in bovine epididymal sperm.
This study was initiated to determine whether factors are present in human sperm-free seminal plasma (HSP) that regulate the uptake and release of carnitine from sperm. Bovine caput epididymal sperm cells accumulated more carnitine than caudal sperm cells. A significant reduction in carnitine uptake by caput sperm was observed in the presence of HSP from normal subjects, but not from three subjects with reduced motility. A factor has been isolated from HSP that inhibits carnitine uptake by caput sperm and has the following properties: it is nondialyzable, stable to freeze-thawing, soluble in 60% ammonium sulfate, and has an approximate molecular weight of 158 kd. These data are consistent with the existence of a relatively high molecular weight protein in HSP responsible for the preservation of carnitine concentrations in sperm.
Carter
A L
AL
Department of Cell and Molecular Biology, Medical College of Georgia, Augusta 30912-3331.
Cho
S H
SH
Bishop
E R
ER
Boldt
J
J
D000818:Animals; D002331:Carnitine / Q000493:pharmacokinetics*; D002417:Cattle; D002851:Chromatography, High Pressure Liquid; D004822:Epididymis; D006801:Humans; D008297:Male; D008970:Molecular Weight; D012661:Semen / Q000032:analysis*; D013081:Sperm Motility; D013094:Spermatozoa / Q000378:metabolism*
D002331:Carnitine