CARDIOVASCULAR EFFECTS OF ATRIOPEPTIN III

心脏的心房合成了一个家族 利尿剂/利钠剂/血管扩张剂多肽称为心房肽。目的 这项研究的目的是研究血液动力学的变化 静脉注射外源性合成心房肽III。目标是了解更多 关于心房肽III在不同条件下的生理学 确定这种荷尔蒙何时可能在调节血液中起重要作用 血压和心输出量。将通过以下方式监测血流变化 在肾脏同时应用定向脉冲多普勒血流测量技术， 肠系膜和后肢(肌肉)阻力床。血压和 心率也将被同步监测，并在 肾、肠系膜和后肢血管床的阻力将是 在每个心动周期期间计算对 在其他大鼠中，脉冲多普勒血流探头将 放置在升主动脉上以测量总心输出量的变化 和总的外周阻力。设计实验的目的是比较 缺水状态与正常状态对心房肽III的反应 水合作用与体积负荷和缺钠条件下与 正常钠摄入量与高钠摄入量相比， 长期使用醛固酮、抗利尿激素或 促肾上腺皮质激素。血浆中心房肽III的水平也将 根据这些生理条件中的每一个在 外源性心房肽的给药III。重要的是了解 更多关于心房肽系统的心血管生理学的顺序 最终研究其在某些特定疾病的病理生理学中的可能作用 钠敏感型或容量敏感型高血压，充血性 心力衰竭、肾功能不全和内分泌失调。

The atria of the heart synthesize a family of diuretic/natriuretic/vasodilator peptides called atriopeptins. The purpose of this investigation is to study hemodynamic changes in response to intravenous exogenous synthetic atriopeptin III. The goal is to learn more about the physiology of atriopeptin III under various conditions to determine when this hormone may be important in the regulation of blood pressure and cardiac output. Blood flow changes will be monitored by means of directional pulsed-Doppler flowmetric technique simultaneously in renal, mesenteric and hindquarter (muscle) resistance beds. Blood pressure and heart rate will also be monitored simultaneously and regional changes in resistance in the renal, mesenteric and hindquarter vascular beds will be calculated during each cardiac cycle for the duration of the response to atriopeptin III. In other rats, the pulsed-Doppler flowprobe will be placed on the ascending aorta to measure changes in total cardiac output and total peripheral resistance. Experiments are designed to compare the responses to atriopeptin III in states of water deprivation vs normal hydration vs volume load and under conditions of sodium deprivation vs normal sodium intake vs high sodium intake and in animals that are being infused chronically with aldosterone, with antidiuretic hormone, or with adrenocorticotropin. Plasma levels of atriopeptin III will also be determined under each of these physiological conditions before the administration of exogenous atriopeptin III. It is important to understand more about the cardiovascular physiology of the atriopeptin system in order to eventually study its possible role in the pathophysiology of certain sodium-sensitive or volume-sensitive forms of hypertension, congestive heart failure, renal insufficiency and endocrine disorders.