AVP MODULATION OF CARDIOVASCULAR RESPONSE TO EXCERCISE

这项研究将确定AVP在调节细胞周期中的作用 猫对运动的心血管反应。具体目标是：(1) 确定电诱导的后肢静态收缩是否 诱导脊髓和全身AVP的增加。如果是这样的话，我们 将确定这些反应是否在一定程度上是由于收缩- 诱发神经内分泌反射。因此，背角和血浆水平 在静息状态和收缩前后测量AVP 收缩肌失神经；(2)研究这种可能性 在肌肉收缩过程中系统释放的AVP有助于 通过对动脉压力感受器反射的作用来影响运动加压反射。 准确地说，AVP使动脉压力感受器敏化的可能性 将在锻炼过程中进行检查。因此，MAP和肾脏的变化 交感神经活动(RSNA)对静态收缩的反应 在恒定的颈动脉窦压力下进行评估。回应将是 比较全身性AVP受体抑制前后的变化。 最后区，或选择性AVP受体阻断后区。 微量注射AVP可引起最后区的AVP阻断 特定的AVP受体拮抗剂；(3)确定AVP是否在 脊髓背角调制减弱运动加压反射 在它的传入手臂上。因此，升压和收缩反应 在适当的前后将监测静态收缩 鞘内注射AVP或其受体拮抗剂或微量注射 这些药物进入脊髓的背角。结果是 这些研究将有助于确定潜在的作用机制。 AVP在运动过程中对心血管系统的影响，并可能允许医生 在可能有害的条件下改变这种多肽的作用 (高血压、心力衰竭或缺血性心脏病)。

This research will determine the role of AVP in modulating the cardiovascular response to exercise in cats. Specific aims are: (1) to determine if electrically-induced static contraction of the hindlimb induces increases in spinal and systemic AVP. If this is the case, we will ascertain if these responses are due, in part, to a contraction- induced neuroendocrine reflex. Consequently, dorsal horn and plasma levels of AVP will be measured at rest and during contraction before and after denervation of the contracting muscle; (2) to investigate the possibility that AVP, released systemically during muscular contraction, contributes to the exercise pressor reflex by its action on the arterial baroreflex. Precisely, the possibility that AVP sensitizes the arterial baroreceptors during exercise will be examined. Thus, changes in MAP and renal sympathetic nerve activity (RSNA) in response to static contraction will be evaluated at a constant carotid sinus pressure. Responses will be compared before and after systemic AVP receptor inhibition, lesion of the area postrema, or selective AVP receptor blockade in the area postrema. AVP blockade in the area postrema will be induced by microinjections of specific AVP receptor antagonists; (3) to determine if AVP acts within the spinal dorsal horn to attenuate the exercise pressor reflex by modulation of its afferent arm. Therefore, the pressor and contractile responses to static contraction will be monitored before and after appropriate intrathecal injection of AVP or its receptor antagonists or microinjection of these drugs into the dorsal horn of the spinal cord. The results of these studies will help identify the mechanisms underlying the action of AVP on the cardiovascular system during exercise and may allow physicians to modify the action of this peptide in conditions where it may be harmful (hypertension, heart failure, or ischemic heart disease).