RECEPTOR REGULATION OF HORMONE SECRETION

激素分泌的受体调节

基本信息

批准号：
3154597
负责人：
ALLAN S SCHNEIDER
金额：
$ 17.02万
依托单位：
ALBANY MEDICAL COLLEGE
依托单位国家：
美国
项目类别：
财政年份：
1985
资助国家：
美国
起止时间：
1985-09-01 至 1987-08-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/3154597
关键词：
action potentials catecholamines chromaffin cells cyclic AMP cyclic GMP depolarizing neuromuscular blocking agent electrophysiology fluorescent dye /probe hormone regulation /control mechanism membrane permeability membrane potentials neural information processing neuroendocrine system radiotracer secretion tissue /cell culture

项目摘要

The long term goal of this project is to elucidate the mechanism of receptor regulation of adrenal hormone secretion in isolated and cultured adrenal chromaffin cells. The chromaffin cell has long been considered a paradigm of stimulus-secretion coupling and much of our general knowledge of cellular secretory mechanisms has been derived from studies of the perfused adrenal gland. The recent availability of isolated and cultured chromaffin cells promises new insights into secretroy mechanisms in general and catecholamine release in particular. The roles of several important receptor mediated membrane responses in regulating secretion will be investigated including: 1) activation of Na, Ca, and cholinergic receptor ion channels, 2) membrane action potential spiking, 3) calcium translocation and 4) alterations in levels of cyclic AMP and cyclic GMP. Chromaffin cells will be isolated by sequential collagenase digestion of bovine adrenal medulla and maintained in culture on collagen coated dishes in Dulbecco's Modified Eagles Medium supplemented with 10% fetal calf serum. Catecholamine secretion will be measured by a (3H) norepenephrine assay and independently by the standard THI fluorescence assay. Membrane electric potential will be monitored by glass microelectrodes and independently using potential sensitive optical probes. Membrane calcium translocation will be monitored by 45Ca tracer techniques and by fluorescent probes. A variety of pharmacological agents will be used to influence ion channels, membrane potential, cyclic nucleological levels, and cholinergic receptors and their corresponding effects upon catecholamine secretion will be determined. An improved understanding of the mechanism and pharmacology of cellular secretion should help in the management of certain endocrine and exocrine diseases having defective secretion, notably cystic fibrosis, hyperinsulinism, acromegaly, and the adrenal medullary tumor, pheochromocytoma. There is also the direct relevance of adrenaline release to pulmonary and cardiovascular function and hypertention.

该项目的长期目标是阐明分离和培养的肾上腺激素分泌的受体调节肾上腺染色体细胞。长期以来，铬蛋白细胞已被认为刺激 - 分泌耦合的范式和我们的许多常识细胞分泌机制的研究是从研究的研究中得出的灌注肾上腺。最近的孤立和培养的可用性一般而言特别是儿茶酚胺释放。几个重要的角色受体介导的调节分泌中的膜反应将是研究包括：1）激活Na，Ca和胆碱能受体离子通道，2）膜动作电势尖峰，3）钙易位和4）循环AMP和环状GMP水平的改变。铬蛋白细胞将通过顺序的胶原酶消化分离牛肾上腺髓质，并在胶原蛋白涂层培养基上保持培养物在Dulbecco的修改后的老鹰培养基中，补充了10％的胎牛血清。儿茶酚胺分泌将通过（3H）去甲肾上腺素测量测定并独立于标准的Thi荧光测定。膜电势将由玻璃微电极和独立使用潜在的敏感光学探针。膜钙易位将由45CA示踪技术和荧光探针。多种药理剂将用于影响离子通道，膜电位，环状核对学水平，和胆碱能受体及其对相应的对将确定儿茶酚胺分泌。对细胞分泌的机制和药理学应有助于管理某些内分泌和外分泌疾病有缺陷的分泌，特别是囊性纤维化，高胰岛素，肢端肥大和肾上腺髓质肿瘤，嗜铬细胞瘤。还有直接肾上腺素释放与肺和心血管功能的相关性和高血压。