Hormonal factors related to the incidence of testicular tumors in male pseudohermaphrodite rats.

Pieces of testicular tumor from male pseudohermaphrodite (tfm) rats were transplanted between the skin and body wall musculature of 4-day-old female, male, and tfm hosts and to the anterior chambers of the eyes of gonadectomized and intact adult tfm, female, and male hosts. These transplants grew in all hosts except normal males. To determine whether these tumors were hormone-dependent, the levels of circulating gonadotropins were measured in all host types to ascertain which were low in the males and high in all of the others. Prolactin, luteinizing hormone (LH), and follicle-stimulating hormone (FSH) levels were measured in intact and castrated normal and tfm rats. Normal males had low levels of prolactin, estrogen, LH, and FSH; however, transplants grew well in other hosts with low titers of these hormones. Except for normal males, all hosts had high serum levels of LH. Thus, testicular tumors in tfm rats appear to be LH-dependent.