No abstract

No abstract

Histochemical methods have been widely used for the detection and localization of hydroxysteroid dehydrogenase activity, mainly in steroid-hormone producing organs and tissues (Baillie, Ferguson & Hart, 1966 (1966).Before incubation, the sections were treated with double-distilled acetone at -25°C for 10 min, and then immersed in three changes of 0-1 m phosphate buffer, pH 7-2, for a total of 10 min. Sections were incubated for 1 hr at 37°C in a medium containing 4-0 ml of the buffer solution, pH 7-2, 0-8 ml aqueous solution of 0-3% nicotinamide adenine dinucleotide (General Biochemicals), 1 ml of 0-1 % aqueous nitro blue tetrazolium (Sigma), and 0-7 ml of 0-16% nico¬ tinamide (Nutritional Biochemicals Corp.) in aqueous solution. The addition of nicotinamide may have enhanced the response, but was not essential. It was omitted with the tissues from the second group of boars.To demonstrate hydroxysteroid dehydrogenase activity, various steroids were used as substrates at a final concentration of 0-1 niM, or 0-5 mM, in the medium. For A5-3/Mvydroxysteroid dehydrogenase the steroids added were dehydroepz'androsterone (dha), 3/?,17/?-dihydroxyandrost-5-ene (androstenediol), dehydroij&zandrosterone sulphate and pregnenolone sulphate; and