[Mechanism of alcoholic testicular damage]

To observe the mechanism of alcoholic testicular damage, in a previous experiment we used weanling male SD rats aged 45 days, weighing about 200 g, and fed a liquid diet (Lieber's) containing 5% ethanol. The latter accounted for 36% of total caloric intake for 7 weeks, but did not result in testicular atrophy. In a later experiment, we used a liquid diet in which ethanol accounted for 46% of the total calorie count. It provided a high-fat, low-protein content which simulated the nutritional background of patients with alcoholic liver diseases. This diet resulted in testicular atrophy. Histological and biochemical changes accompanying this experimental testicular atrophy included the following: 1) The testes of alcohol-fed animals contained smaller seminiferous tubules with reduced numbers of total cells, but no degeneration was seen in the spermatids. 2) In the peritubular wall of the seminiferous tubules, we observed curvature, irregularities, infolding of the basement membrane, and lamellation of the lamina densa, as well as hyperplasia of collagen fibers in the tunica propria. 3) In the cytoplasm of the Sertoli cells, deposits of gigantic fat droplets and stratification of the mitochondria were observed. The permeability of the Sertoli cell tight junction was confirmed using the Lanthanum method. 4) Testosterone levels in both the serum and testes declined. 5) Lactate dehydrogenase-X (LDH-X) activity in the testes declined. 6) Low Km alcohol dehydrogenase (ADH) activity localized in the testicular interstitial tissue was increased. These results indicate that the composition of three major nutritional elements as well as alcohol concentration are important in the mechanism of alcoholic testicular damage, and this damage affects both the testicular interstitial cell and the seminiferous tubules, particularly the Sertoli cells and peritubular wall of the latter. In addition, the findings suggest that ADH is involved in alcohol metabolism in the interstitial cells of the testes.