Oxidative metabolism of bovine spermatozoa

Abstract

Suspensions of washed bovine sperm (phosphate buffer, pH 7.4) were incubated at 37 °C for 1 h with pyruvate-3-14C and in some cases, with oxaloacetate. Oxygen consumption and 14CO2 evolution were measured. Radioactive citrate, malate, fumarate, α-ketoglutarate, and oxaloacetate were found following incubation. The latter two compounds were positively identified by melting-point and specific-activity determinations of their 2,4-dinitrophenylhydrazone derivatives. The results indicate citric acid cycle activity in bull sperm. Oxygen consumption and the evolution of 14CO2 from pyruvate-3-14C tended to decline when oxaloacetate was added to the sperm suspensions.