TESTICULAR MORPHOLOGY AND ANDROGEN PROFILES FOLLOWING TESTICULAR ISCHEMIA IN RAMS

Arteriosclerotic changes were induced in the internal spermatic artery of rams to determine whether there is a link between this condition a nd some pathological conditions of the testes, similar to those that c ause infertility in men. Eight weeks after the induction of testicular ischaemia, blood plasma was collected simultaneously from the jugular and spermatic veins after an LH injection (10 mu g) and assayed for t estosterone. The rams were then castrated and sections of the testis, ductuli efferentes and spermatic cord were examined quantitatively and qualitatively. Vascular disturbance decreased the percentage of norma l spermatogenic epithelium (P < 0.01) and the diameter of the seminife rous tubules (P < 0.001). These effects were accompanied by an increas e in the percentage of the interstitial region within the testis (P < 0.05). Macrophages, lymphocytes and other inflammatory cells became nu merous in the interstitium as damage to the seminiferous epithelium pr ogressed. The most striking feature of the ischaemic testis was the fo cal damage of the spermatogenic epithelium, that is, sections of the s ame testis exhibited both normal and germ cell-depleted seminiferous t ubules. Concentrations of testosterone in peripheral plasma were not s ignificantly altered by either unilateral or bilateral testicular isch aemia; however, the concentration of testosterone was higher in the ex perimental spermatic vein than in the contralateral spermatic vein (P < 0.05) as was the ratio of LH:testosterone (P < 0.05). Unilateral vas cular disturbance of the testis did not cause damage in the contralate ral testis. The ductuli efferentes of these rams also showed structura l changes as a result of vascular disturbance. The tubules of the most proximal regions were reduced in calibre compared with the control ti ssue (P < 0.005) and pigment-laden macrophages had invaded the lumina, the epithelium of the ducts and the interstitium. These morphological and endocrine profiles that were induced in rams are typically seen a mong infertile men. These similarities suggest that vascular disturban ce may be implicated in the formation of some gonadal pathologies that cause infertility in men.