Endocrine effects of early non-union of testis and epididymis and of cryptorchidism in the rat.

The aim of this study was to explore possible endocrine effects of early non-union of testis and epididymis. In 16 days old Sprague-Dawley rats the testis and epididymis were separated to the level of the inferior epididymis artery (non-union operation). Animals were killed at intervals from 30-58 days, and the plasma concentrations of total testosterone, total estrogens, LH, FSH and PRL were measured. The testes were studied by light microscopy. Groups of rats made cryptorchid and sham-operated rats were used as controls. Although their testes were scrotal, the non-union operated animals had testosterone and estrogen concentrations similar of cryptorchid animals, and significantly (p less than 0.05) lower than sham-operated animals. The LH- and FSH-concentrations were significantly (p less than 0.05) elevated suggesting a primary lesion in both Leydig- and Sertoli-cells. Towards puberty FSH increased in the non-union operated animals, while FSH values declined in the cryptorchid and sham-operated animals. These FSH-patterns probably reflect the existence of different pathogenic mechanisms in the non-union operated rats and the rats with cryptorchid testes.