Histochemistry of normal and ethionine-treated rat testis

Abstract

Testicles of mature rats were seen to be very sensitive to a low level of DL-ethionine (0.1% in the diet) for a period varying from seven to ten months, while the drug failed to interfere with the body growth. By means of histoenzymological techniques, the fate of some energetic and oxidative enzymes was tested both in control and treated animals: Alkaline phosphatase, which was evident in the connective tissue membrane of the tubuli, was seen to increase in the atrophic testicles, perhaps as a consequence of a decrease in tubular diameter. Acid phosphatase, weakly visible in control rat, showed a high activity in the hyperplastic interstitial tissue which accompany the inhibition of spermatogenesis produced by ethionine treatment. Adenosine triphosphatase showed a decreasing activity in the thick basement membrane of the treated rats whereas a strong deposit was still in the interstitial structures. Thiamine pyrophosphatase which was demonstrated in all stages of spermatogenesis in the mature testes showed a net reduction of enzymatic activity in the damaging germinal cells. α-Glycerophosphate dehydrogenase, Glucose-6-phosphate dehydrogenase, and 3β-hydroxysteroid dehydrogenase were absent in the ethionine treated rats, although important in the metabolic pathway of steroidogenesis. Lactic dehydrogenase was tested with two different substrates=Potassium Lactate and DL-α-hydroxyvalerate. In the ethionine fed rats, the enzyme activity disappears in the tubuli as well as in the interstitial cells.