The binding sites of antisera generated in the guinea pig against ovine luteinizing hormone (oLH) and its two subunits (oLHalpha and oLHbeta) have been localized in rat anterior pituitaries taken from normal or castrated males and from ovariectomized females with the peroxidase-labeled antibody method, using light and electron microscopy. With the light microscope, the cells positive with antis...

The influence of testosterone on gonadotropin-releasing hormone (GnRH) secretion was assessed indirectly by altering the serum testosterone concentration of male rats and measuring GnRH release from their incubated hypothalami 1 wk later.GnRH release from hypothalami of castrated rats was 13.4+/-1.2 (SE) pg/h, compared to 35.3+/-3.8 pg/h from hypothalami of intact rats (P < 0.001). GnRH release...

Inbred AxC strain male and female rats were fed 0.025% 7V-2-fluorenyldiacetamide in the diet. Growth hormone was administered to intact and castrated animals to determine its effect on carcinogenesis and cirrhosis of the liver. Growth hormone increased the incidence of hyperplastic and neoplastic lesions and cirrhosis in both castrated males and castrated females, but it did not exert any effec...

Experimentally obese virgin female C3H mice showed a more marked increase and an earlier incidence of mammary tumors than did normal (weight) controls. When castrated, such animals showed a decrease in tumorigenesis, below that of unoperated obese animals or mice of normal weight. However, such obese castrated animals demonstrated a tumor incidence significantly greater than normal weight, cast...

Sarcoma 37 cells grew more rapidly in castrated male mice than in controls of the same genotype; however, this effect of castration was dependent on the host genotype. Among inbred YS/Wf mice, tumor weight was increased only in castrated yellow Ay/a males and not in the comparable black a/a males. In contrast, mean tumor weight was increased in both yellow Avy/a and black a/a castrated males of...

Estrogen-binding proteins have been characterized in variants of the MTW-9B rat mammary tumor in an attempt to determine the functional significance of the low affinity cytosolic estrogen binder. In vivo selection of tumor variants was carried out by transplant of the tumor into intact and castrated male and female Wistar-Furth rats for four or five successive transplant generations. Tumors tha...

Alpha 2u Globulin is a protein synthesized in the liver, secreted into the serum, and excreted in the urine of mature male rats. The effects of androgens and estrogens on the level of the messenger RNA coding for the male rat hepatic protein have been investigated. Castrated male rats have reduced levels of alpha 2u globulin in serum and liver cytosol, as measured by a radial immunodiffusion as...

Myocardial ischemia is the leading cause of death in both men and women; however, very little information exists regarding the effect of testosterone on the response of myocardium to acute ischemic injury. We hypothesized that testosterone may exert deleterious effects on myocardial inflammatory cytokine production, p38 MAPK activation, apoptotic signaling, and myocardial functional recovery af...

The levator ani muscle (LA) of the rat is highly androgen-sensitive and, like all skeletal muscles, deteriorates structurally and functionally when denervated. In order to elucidate the interplay of neural and endocrine influences, the separate and combined effects of denervation and castration on myofiber cross-sectional area and nuclear populations were quantitatively studied. In one group of...