Metabolism of testicular spermatozoa and characteristics of testicular fluid collected from conscious rams.

Abstract

Summary. A procedure is described for the collection of spermatozoa and fluid from the testes of conscious rams over long periods of time. Spermatozoa and fluid are produced at a steady rate. The fluid is isosmotic with blood plasma but contains more potassium and less sodium. Testicular spermatozoa differ from ejaculated spermatozoa by converting a higher percentage of the utilized glucose to carbon dioxide and a lower percentage to lactic acid. They are resistant to cold shock, and can be stored at 1° C in testicular fluid for up to 6 days without significant mortality. The metabolic pattern of stored testicular spermatozoa resembles that of ejaculated spermatozoa, but differs from that of freshly collected testicular spermatozoa. Freshly collected testicular spermatozoa are immotile, but a small degree of motility can be induced either by increasing the pH of testicular fluid to between 7·5 and 8·5, or by storage at 1° C in testicular fluid. The immotility of fresh testicular spermatozoa is not due to lack of adenosine triphosphate since this compound is present in similar concentrations in both testicular and ejaculated spermatozoa. No evidence was obtained for the presence of a pentose cycle (hexose monophosphate shunt) in either testicular or ejaculated spermatozoa. Testicular fluid stimulates the oxygen uptake of both kinds of spermatozoa.