HORMONES, HORMONE RECEPTORS, AND AGING - III AGING AND HUMAN ENDOCRINE REGULATION

我们的临床研究收集了有关脑下垂体分泌功能的数据 与性腺、肾上腺、甲状腺、催乳素和生长激素有关 对正常衰老的人类的调节。我们最新的发现是 生长激素(GH)和生长抑素-C(Sm-C)对GRF(生长)的反应 激素释放因子)、促肾上腺皮质激素和皮质醇对CRF的反应性 (促肾上腺皮质激素释放因子)不随年龄变化，而CRF 介导的DHEA分泌大大减少，表明独立 皮质醇和脱氢表雄酮的分泌调节。基础和促性腺激素释放激素刺激催乳素 与年轻男性相比，年长男性的分泌物增加。我们最近做了 测量了大鼠的睾酮、睾酮结合和促性腺激素 患有和不患有慢性病的不同年龄段的男性 数据显示，总的和 血浆游离睾酮(T)随增龄而升高，并伴有FSH升高，但 不是左撇子。疾病的影响是深远的(与疾病的影响相比 增龄)良性疾病患者的游离(但不是全部)T降低， 癌症患者的游离T和总T均降低。继续 研究涉及循环中的雌激素和 雄激素、心血管疾病的发病率和已知的心血管疾病 风险因素，如脂蛋白谱、肥胖和体脂 分发。我们计划对时间调节和反馈进行研究 ACTH-肾上腺轴在未来一年的敏感性。

Our clinical studies gather data on pituitary secretory function as it relates to gonadal, adrenal, thyroid, prolactin, and growth hormone regulation in normal aging humans. Our most recent findings were that growth hormone (GH) and somatomedin-C (Sm-C) responsiveness to GRF (growth hormone releasing factor) and ACTH and cortisol responsiveness to CRF (corticotropin releasing factor) are unaltered with age, whereas CRF mediated DHEA secretion is greatly reduced, suggesting independent regulation of cortisol and DHEA secretion. Basal and TRH stimulated Prl secretion are increased in older vs. younger men. We have recently measured testosterone, testosterone binding, and gonadotropins in a large group of men of various ages with and without chronic illness and have shown that there is modest, but significant, decrease in both total and free plasma testosterone (T) with age, accompanied by increased FSH, but not LH. The effects of illness were a profound (compared with effects of aging) lowering of free (but not total) T in patients with benign disease, and lowering of both free and total T in patients with cancer. Continuing studies address the interrelationships among circulating estrogens and androgens, incidence of cardiovascular disease, and known cardiovascular risk factors, such as lipoprotein profile, obesity, and body fat distribution. We plan studies of the temporal regulation and feedback sensitivity of the ACTH-adrenal axis in the coming year.