Incorporation of selenium-75 into semen and reproductive tissues of bulls and rams.

After intramuscular injections of 500 muCi 75Se, semen was collected periodically over a 63-day period from a selenium-deficient and a selenium-injected ram which were then killed for collection of the reproductive organs for the gel filtration studies. Testes, accessory glands and semen were also obtained from a bull injected intravenously with 75Se. Gel filtration (Sephadex G 150) of ram testis cytosol resulted in 4 75Se peaks (Ve/Vo ratios of 1 X 1, 1 X 5, 2 X 3, 2 X 9). In the selenium-injected ram the glutathione peroxidase (GSH-Px) peak (Ve/Vo 1 X 5) predominated, but in the selenium-deficient ram, radioactivity of the GSH-Px peak was less than that of the higher molecular weight peak (Ve/Vo 1 X 1). Gel filtration chromatograms of bull testis cytosol yielded 5 75Se peaks (Ve/Vo 1 X 1, 1 X 5, 1 X 9, 2 X 4, 2 X 8). In chromatograms of ram seminal plasma on Sephacryl S-200 there were 2 major (Ve/Vo 1 X 4, 1 X 1) and 2 minor peaks (Ve/Vo 1 X 7, 2 X 4). 75Se increased with time up to 49 days after injection in all peaks. 75Se-labelled bull seminal plasma yielded 2 75Se peaks (Ve/Vo 1 X 1, 1 X 4) which corresponded to the major peaks of ram seminal plasma. Bull and ram seminal plasma GSH-Px activities per mg protein were comparable (28 and 29 nmol NADPHox/min, respectively), but when expressed per ml seminal plasma, activity of the bull was more than 7 times the highest activity of ram seminal plasma (2908 and 385 nmol NADPHox/min, respectively).(ABSTRACT TRUNCATED AT 250 WORDS)