RESUMO
To determine mechanisms of endocrine dysfunction in patients with testicular cancer, we performed static and dynamic testing of the hypothalamic-pituitary-testicular axis and testicular exocrine function in 13 patients and 11 normal control subjects, as well as in vitro studies of tumor tissue and remaining adjacent "normal" testicular tissue in the 13 patients. In tumor tissue, we demonstrated (a) elevated concentrations of total serum estradiol and serum estradiol not bound to sex hormone-binding globulin, (b) impaired spermatogenesis and sperm motility, and (c) blocking of multiple enzymes necessary for steroidogenesis. The data were consistent with a paracrine-endocrine mechanism in which tumor-produced human chorionic gonadotropin stimulates production of estradiol by "normal" testicular tissue but not tumor tissue, and the high estradiol levels then result in impaired spermatogenesis.
Assuntos
Doenças do Sistema Endócrino/etiologia , Neoplasias Testiculares/complicações , Adulto , Gonadotropina Coriônica/sangue , Técnicas de Cultura , Disgerminoma/complicações , Doenças do Sistema Endócrino/metabolismo , Estradiol/biossíntese , Hormônios/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Hormônios Hipofisários/metabolismo , Contagem de Espermatozoides , Motilidade dos Espermatozoides , Teratoma/complicações , Neoplasias Testiculares/metabolismo , Testículo/metabolismo , Testosterona/metabolismoRESUMO
Hypothalamic-pituitary-adrenal function in a well-defined, carefully selected group of 25 patients with extrinsic asthma was assessed by measuring plasma levels of adrenocorticotropic hormone (ACTH) and of 11-deoxycorticol after administration of metyrapone and by measuring the level of cortisol following stimulation with cosyntropin. No difference was demonstrated between asthmatic subjects and 20 normal age-matched controls. In addition, neither the response of the level of ACTH nor of 11-deoxycortisol correlated with the duration of asthma or the severity as assessed in 23 patients by tests of pulmonary function. We conclude that there is no abnormality in hypothalamic-pituitary-adrenal function in patients with extrinsic asthma, and we suggest that previous data suggesting such an abnormality may reflect heterogeneous groups of patients, inaccurate methods, and the variability of normal responses to ACTH and stimulation with metyrapone.
Assuntos
17-Hidroxicorticosteroides/sangue , Hormônio Adrenocorticotrópico/sangue , Asma/fisiopatologia , Cortodoxona/sangue , Sistema Hipotálamo-Hipofisário/fisiopatologia , Sistema Hipófise-Suprarrenal/fisiopatologia , Adolescente , Adulto , Feminino , Humanos , Masculino , Metirapona , Pessoa de Meia-IdadeRESUMO
The effect of stimulating atrial receptors on the concentration of ACTH in jugular venous blood was examined in dogs anaesthetized with chloralose. The atrial receptors were stimulated by stretching the pulmonary vein-atrial junctions and the atrial appendage. In 13 experimental runs in 9 dogs, it was found that the concentration of ACTH fell in 11 and remained unchanged in 2. The average concentration during control periods was 76.5 +/- 13.6 (pg/ml) and that during stimulation was 60.0 +/- 11.8 (pg/ml). This difference was statistically significant (p less than 0.05; 2 tailed t test). Cutting (2 dogs) or cooling the cervical vagi (3 dogs) abolished this response. It is concluded that stimulation of left atrial receptors reduces the concentration of ACTH in plasma.