EFFECT OF HEAVY MUSCULAR WORK ON THE MORPHOLOGY AND HISTOCHEMISTRY OF THE RAT TESTIS

Abstract

ABSTRACT The effect of short- and long-term muscular work on the Leydig cells of the rat was studied. The rats were allowed to run in a rotating wire cylinder for various periods. The amount of stress was evaluated by the involution of the thymus, ulceration of the gastric mucosa, enlargement of adrenal glands and their lipid and catecholamine contents. After a short-term experiment, periods of 16 + 10 hours' running with rest for 10 hours in between, accessory genital organs were slightly involuted 4 to 8 days following the stress. The testes were histologically and histochemically intact. Similar results were obtained after a long-term experiment, comprising continuous daily running for 10 hours over a period of 12 days. In a progressive long-term experiment, viz. daily running until exhaustion for 14 days, temporary degeneration of the Leydig cells occurred: the percentage of interstitial tissue and the size of the nuclei of the Leydig cells diminished and the number of degenerating Leydig cells significantly increased. Oxidative enzyme activity was markedly suppressed. DPN-diaphorase and β-hydroxybutyric dehydrogenase activity were very markedly decreased. The involution of the accessory genital organs was more pronounced than in the two former experiments. All these phenomena reverted to normal within ten days. In every experiment the seminiferous tubules remained histologically normal.