Peptidergic modulation of mechanotransduction in rat arterial baroreceptors.
Peptidergic modulation of mechanotransduction in rat arterial baroreceptors.
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大鼠动脉压力感受器中机械转导的肽能调节。
DOI：
10.1161/01.res.66.3.804
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发表时间：
1990
影响因子：
20.1
通讯作者：
Andresen,MC
中科院分区：
文献类型：
--
作者：
Yang,MY;Andresen,MC
定期放电压力感受器在大鼠体外主动脉弓制备暴露于增加浓度的四种血管活性肽之一：血管紧张素II，精氨酸加压素，心钠素，或P物质。缓慢斜坡的压力诱发放电反应在单纤维压力感受器。瞬时放电频率与主动脉直径和压力同时测量。在血管紧张素II或精氨酸加压素引起的收缩过程中，压力感受器直径阈值（Dth）降低，压力阈值（Pth）有增加的趋势，这些作用被硝普钠减弱或消除。心房利钠因子和P物质本身对血管直径或压力感受器放电没有影响。在用中等浓度苯肾上腺素（10（-8）M）预收缩的标本中，心房利钠因子减少苯肾上腺素引起的收缩，增加Dth，减少Pth。即使在高浓度下，P物质在减少苯肾上腺素收缩和改变压力感受器放电方面的效果也不如心房利钠因子。压力感受器增益不受任何这些肽。因此，平滑肌张力的变化通过1）血管压力-直径关系和2）压力感受器阈值要求（Pth和Dth）的变化改变机械转导。压力感受器机械阈值（Dth）的变化降低了预期血管壁力学变化对Pth的影响。Pth反映了血管壁和Dth变化的净效应。收缩期Pth升高，扩张期Pth降低。血管活性肽作用期间Dth及其选择性（增益无变化）的变化与压力感受器的快速重置非常相似。我们建议，血管平滑肌与主动脉压力感受器平行排列，并且在血管直径持续变化期间，共同的代偿机制调节Dth。平滑肌的激活和跨壁压的降低将减少压力感受器的负荷，并且所提出的代偿机制将倾向于通过降低Dth来保持放电恒定。然而，我们的实验，不能区分假设的局部微观力学变化的耦合或变化的压力感受器神经元本身的兴奋性作为基础的Dth调整。
Regularly discharging baroreceptors in a rat in vitro aortic arch preparation were exposed to increasing concentrations of one of four vasoactive peptides: angiotensin II, arginine vasopressin, atrial natriuretic factor, or substance P. Slow ramps of pressure evoked discharge responses in single-fiber baroreceptors. Instantaneous discharge frequency was measured simultaneously with aortic diameter and pressure. During constriction induced by angiotensin II or arginine vasopressin, baroreceptor diameter threshold (Dth) decreased and pressure threshold (Pth) tended to increase; these effects were reduced or eliminated by nitroprusside. Atrial natriuretic factor and substance P by themselves were without effect on vessel diameter or on baroreceptor discharge. In preparations preconstricted with a moderate concentration of phenylephrine (10(-8) M), atrial natriuretic factor reduced the phenylephrine-induced constriction and increased Dth and decreased Pth. Substance P, even at high concentrations, was less effective than atrial natriuretic factor in reducing phenylephrine constriction and in altering baroreceptor discharge. Baroreceptor gain was unaffected by any of these peptides. Thus, changes in smooth muscle tone altered mechanotransduction by shifts in 1) the vessel pressure-diameter relation and 2) baroreceptor threshold requirements (Pth and Dth). Changes in the baroreceptor mechanical threshold (Dth) reduced the effects on Pth expected from changes in vessel wall mechanics. Pth reflects the net effects of vessel wall and Dth changes. Pth generally increased during constrictions and decreased during dilations. The changes in Dth and their selectivity (no changes in gain) during vasoactive peptide action closely resemble rapid resetting of baroreceptors. We propose that vascular smooth muscle lies in a parallel arrangement with aortic baroreceptors and that a common compensatory mechanism regulates Dth during sustained changes in vessel diameter. Activation of smooth muscle and reductions in transmural pressure would reduce loading of baroreceptors, and the proposed compensatory mechanism would tend to keep discharge constant by decreasing Dth. Our experiments, however, cannot distinguish between hypotheses for local micromechanical changes in coupling or for changes modulating excitability within the baroreceptor neuron itself as the basis for Dth adjustments.
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精氨酸加压素对哺乳动物的主动脉和心脏压力感受器敏感。
DOI：
10.1113/jphysiol.1986.sp016185
发表时间：
1986
期刊：
The Journal of Physiology
影响因子：
--
作者：
F. Abboud;P. Aylward;J. Floras;B. N. Gupta
通讯作者：
B. N. Gupta
心房肽激活迷走神经抑制反射抑制肾交感神经活动。
DOI：
10.1152/ajpheart.1986.251.6.h1252
发表时间：
1986
期刊：
The American journal of physiology
影响因子：
--
作者：
Thoren,P;Mark,AL;Morgan,DA;O'Neill,TP;Needleman,P;Brody,MJ
通讯作者：
Brody,MJ
主动脉压力感受器体外快速重置。
DOI：
10.1152/ajpheart.1983.244.5.h672
发表时间：
1983
期刊：
The American journal of physiology
影响因子：
--
作者：
P. Munch;M. Andresen;A. Brown
通讯作者：
A. Brown
α-人心房钠尿肽对动脉压、主动脉神经活动和主动脉直径相互关系的影响
DOI：
10.11501/3086544
发表时间：
1991
期刊：
Federation proceedings
影响因子：
--
作者：
廣岡 良隆
通讯作者：
廣岡 良隆
蛇纺锤体感觉区的结构及其在拉伸过程中的位移。
影响因子：
2.5
作者：
Y. Fukami;C. Hunt
通讯作者：
C. Hunt