HORMONES AND AGING--HYPOTHALAMIC-PITUITARY FUNCTION IN EXPERIMENTAL ANIMALS

许多激素分泌和组织对激素的反应依赖于 在老年动物中，细胞膜受体转导被钝化 与年幼的动物相比。荷尔蒙反应的这种变化是 经常是由于刺激水平或比率的变化 GTP结合蛋白(Gs)和抑制性GTP结合蛋白(GI) 在细胞内介导许多膜结合的受体反应。我们有 我一直在研究衰老对G蛋白的影响 脂肪细胞环化酶介导儿茶酚胺受体的组成 肝细胞膜，以及最近，开始了对 衰老对骨骼肌等组织对生长激素反应的影响 睾酮集中在EF-1α上，这是一种关键的G蛋白 核糖体中蛋白质合成的中介体。过去的活动 一年来，主要致力于方法的开发和优化 环化酶介导G蛋白复合体EF-1α信使核糖核酸的新分析 检测基因激活情况，并检测组织中EF-1α蛋白的表达。

Many hormone secretion and tissue responses to hormones that depend on cell membrane receptor transduction are blunted in old animals when compared to young animals. Such changes in hormonal responses are frequently due to alterations in the levels or ratios of stimulatory GTP-binding proteins (Gs) and inhibitory GTP binding proteins (Gi ) which mediate many membrane-bound receptor responses intracellularly. We have been conducting investigations of the effects of aging on the G-protein components of cyclase mediated catecholamines receptors in fat cell and hepatic cell membranes, and, more recently, have initiated studies of the effects of aging on responses of skeletal muscle and other tissues to GH and testosterone concentrating on EF-1alpha, a G protein which is a key mediator of protein synthesis at the ribosome. Activities in the past year have been devoted mainly to methods development and optimization of new assays for cyclase mediating G-protein complexes, for EF-1alpha mRNA to detect gene activation, and for EF-1alpha protein in tissue.