NEUROTRANSMITTERS AND CENTRAL CONTROL OF BLOOD PRESSURE

孤束核(NTS)已被广泛研究 在生理功能和组织化学方面；但很少有 已知这些功能与推定的 NTS中确定的发射机。了解这种关系可能会 有助于理解其中一些生理功能是如何调节的 并相互集成，可以揭示潜在的机制 高血压的成因及对血压的控制 从药理上讲。因此，这个项目的目标将是确定 10种神经递质与6种生理功能的关系 (血压、心率、呼吸频率、大脑皮层活动、 胃运动和交感神经活动)由NTS调节。 将特别强调压力感受器反射和 确立L-谷氨酸在其中的整体作用 条件反射。预计每个推定的递质都会被显微注射 会引起不同的生理反应和 各自的对抗者将阻止这些反应。那些天使论者 它们在生理状态下会引起血压的变化和 将进一步研究心率，以确定它们与 压力感受器反射。那些假定的发射器构成了 压力感受器反射将通过它们的拮抗剂的能力来识别 阻断反射并产生神经性高血压，是一个不变的 中枢性压力感受器反射中断的急性后果 在外围。为释放相关物质提供生理学证据 压力感受器传入(或其他迷走神经传入)的递质， 将通过以下方法寻求对注射激动剂的超敏感 单侧牙周膜摘除后不同时间剂量反应的研究 结节神经节。因为工作的一个主要焦点将是中央 在NTS中控制血压，改变对 活跃于心血管调节的激动剂(如上所述)将是 寻求一种形式的自发性高血压，自发性 高血压大鼠。

The nucleus tractus solitarius (NTS) has been extensively studied with respect to its physiologic functions and histochemistry; yet little is known of the relationship between those functions and the putative transmitters identified in the NTS. Knowledge of such relationships could aid in understanding how some of those physiologic functions are mediated and integrated with each other and could reveal potential mechanisms for the genesis of hypertension and for controlling blood pressure pharmacologically. The goal of this project, then, will be to determine relatioships between ten neurotransmitters and six physiologic functions (blood pressure, heart rate, respiratory rate, electrocortical activity, gastric motility, and sympathetic nerve activity) modulated by the NTS. Particular emphasis will be placed on the baroreceptor reflex and on establishing the integral role played by L-glutamate in mediating that reflex. It is anticipated that each putative transmitter microinjected into the NTS will elicit a distinct profile of physiologic responses and that respective antagonists will block those responses. Those angonists which produce, in their physiologic profile, changes in blood pressure and heart rate will be further studied to determine their relationship to the baroreceptor reflex. Those putative transmitters integral to the baroreceptor reflex will be identified by the ability of their antagonists to block the reflex and to produce neurogenic hypertension, an invariable acute result of interruption of the baroreceptor reflex centrally or peripherally. To provide physiologic evidence for release of the relevant transmitters from baroreceptor afferents (or other vagal afferents), supersensitivity to the injection of the agonists will be sought by studying their dose responses at intervals after the unilateral removal of the nodose ganglion. Since a major focus of the work will be the central control of blood pressure in the NTS, changes in the sensitivity to agonists active in cardiovascular regulation (as identified above) will be sought in one form of spontaneous hypertension, the spontaneously hypertensive rat.