Effect of human chorionic gonadotrophin on the dog seminiferous tubule, with and without experimental unilateral cryptorchism.

The effect on human chorionic gonadotrophin (HCG) on the testes of pubertal and postpubertal Beagle dogs was studied, in the one instance in bilaterally normotopic testes and in the other on the still scrotally located gonad of dogs which had been subjected to unilateral experimental cryptorchism. The area of the cross-sectioned seminiferous tubules served as a parameter for evaluating the effect of HCG. Administration of therapeutic doses of HCG produced, in animals with bilaterally normotopic testes, a marked diminution of the area of the seminiferous canals. This means that HCG application at normal dosage impairs the seminiferous tubules in the dog. In animals with unilateral cryptorchism, HCG application produced no significant change in the tubule area of the scrotally located testis beyond that which is ascertainable anyway on the orthotopic testis following translocation of the contralateral gonad to within the abdominal cavity. Hence, HCG does not influence the degenerative change in the orthotopic testis in experimental unilateral cryptorchism. Rather, an adverse effect of HCG on the seminiferous tubule is evident, independently of the hitherto published reports of successfully attained descent.