Mechanisms of respiration-induced changes in vasomotor control exerted by rostral ventrolateral medulla

Author:

Cox B. F.1,Brody M. J.1

Affiliation:

1. Department of Pharmacology, University of Iowa College of Medicine, Iowa City 52242.

Abstract

Efferent and afferent mechanisms involved in the differential depressor response to inactivating rostral ventrolateral medulla (RVLM) under conditions of normal (2.5 ml) and reduced (1.5 ml) tidal volume were examined in urethan-anesthetized rats. Under conditions of reduced tidal volume, bilateral microinjection of lidocaine (200 nl, 4%) into RVLM produced an attenuated fall in both mean arterial pressure (MAP) and renal sympathetic nerve activity (RSNA) despite the fact that base-line levels of both are unchanged. The specificity of the differential response was tested by examination of regional hemodynamics. Microinjecting lidocaine into RVLM produced an attenuated fall in renal, mesenteric, and hindquarter vascular resistances in parallel with the attenuated fall in MAP produced by reducing tidal volume. Microelectrode stimulation of RVLM produced an increase in resistance in all three vascular beds. Of the neural sensory systems examined, both vagal and chest wall afferents appear to be involved in mediating the differential depressor response. These results demonstrate the importance of afferent sensory input to the medulla in determining sites of generation and maintenance of sympathetic vasomotor tone.

Publisher

American Physiological Society

Subject

Physiology (medical),Physiology

同舟云学术

1.学者识别学者识别

2.学术分析学术分析

3.人才评估人才评估

"同舟云学术"是以全球学者为主线,采集、加工和组织学术论文而形成的新型学术文献查询和分析系统,可以对全球学者进行文献检索和人才价值评估。用户可以通过关注某些学科领域的顶尖人物而持续追踪该领域的学科进展和研究前沿。经过近期的数据扩容,当前同舟云学术共收录了国内外主流学术期刊6万余种,收集的期刊论文及会议论文总量共计约1.5亿篇,并以每天添加12000余篇中外论文的速度递增。我们也可以为用户提供个性化、定制化的学者数据。欢迎来电咨询!咨询电话:010-8811{复制后删除}0370

www.globalauthorid.com

TOP

Copyright © 2019-2024 北京同舟云网络信息技术有限公司
京公网安备11010802033243号  京ICP备18003416号-3