Baroreceptor regulation of heart rate in baboons during different behavioral states.
Baroreceptor regulation of heart rate in baboons during different behavioral states.
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不同行为状态下狒狒心率的压力感受器调节。
DOI：
10.1152/ajpregu.1981.241.5.r277
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发表时间：
1981
期刊：
影响因子：
--
通讯作者：
Scher,AM
中科院分区：
文献类型：
--
作者：
Stephenson,RB;Smith,OA;Scher,AM
史蒂芬森，R.B.，0.A·史密斯和AM&Her。不同行为状态下狒狒心率的压力感受器调节。上午好。J.Physiol.241(监管综合公司物理。10)：R277-R285,1981。-研究了在睡眠(S)、食物强化的杠杆挤压(LP)、进食(E)和车轮转动(WT)这四种温和的动态腿部运动(WT)(一种通过避免电击加强的动态腿部运动)下，狒狒的心率(HR)对血压正弦变化的反应。在降主动脉上以0.032-0.18赫兹的频率进行周期性刺激，可引起收缩压随HZ毫米汞柱变化。反射敏感性，表现为单位收缩压变化的心率在S期间最大，在WT期间最小，在LP和E期间居中。这些敏感性的差异在用心率间期而不是HR来评估时更加明显。这种差异导致了四种行为状态下控制心率的不平等，当敏感度以分数而不是绝对的速度或间期变化计算时，这种差异就消失了。由于S、S、LP和E组的反射反应时滞显著小于WT组，因此我们认为S组、Lp组和E组的迷走神经(快)效应可能比交感神经(慢)效应占优势，而WT组则不明显。相应地，迷走神经对反射反应的贡献(用心得安阻断P-肾上腺素能后的灵敏度测量)在S最大，在WT最小，而交感神经的贡献(用阿托品阻断胆碱能后的明显)在四种行为状态下很小且相等。压力感受器或心脏的非线性(饱和)不能解释WT时反射敏感性降低的原因，因为在WT过程中，即使通过收缩下腔静脉降低血压或心得安降低心率，反射敏感性仍然很低。我们得出结论，不同行为状态之间的敏感性差异是压力感受器反射迷走神经成分中枢调节的结果。
STEPHENSON, R. B., 0. A. SMITH, AND AM &HER. Baroreceptor regulation of heart rate in baboons during different behavioral states. Am. J. Physiol. 241 (Regulatory Integrative Comp. Physiol. 10): R277-R285, 1981.-Heart rate (HR) responses to sinusoidal changes in blood pressure were studied in baboons during four states: sleep (S), lever pressing (LP) reinforced by food, eating (E), and wheel turning (WT), a mild dvnamic leg exercise reinforced by shock avoidance. Cyclical i& ‘lation at frequencies of 0.032-0.18 Hz of a cuff implanted on the descending aorta caused systolic pressure to vary by HZ mmHg. Reflex sensitivity, expressed as the change in HR per unit change in systolic pressure was greatest during S, least during WT, and intermediate during LP and E. These differences in sensitivity became more pronounced when assessed by using interval between heart beats rather than HR. This discrepancy resulted f&m the unequal control HR in the four behavioral states, and it disappeared when sensitivity was computed Erom fractional rather than absolute changes in rate or interval. Because time lag of reflex responses was significantly less during, S, LP, and E than during WT, dominance of vagal (faster) over sympathetic (slower) effects was considered likely during S, LP, and E but not during WT. Accordingly, vagal contributions to reflex responses (shown by sensitivity measurements after P-adrenergic blockade with propranolol) were largest in S and smallest in WT, whereas sympathetic contributions (apparent after cholinergic blockade with atropine) were small and equal in the four behavioral states. Nonlinearity (saturation) of baroreceptors or the heart could not account for depressed reflex sensitivity during WT, because reflex sensitivity remained low during WT even when blood pressure was lowered by constriction of the vena cava or when HR was lowered by propranolol. We conclude that differences in sensitivity among the behavioral states result from central modulation of the vagal component of the baroreceptor reflex.