Cardiovascular responses to graded reductions in hindlimb perfusion in exercising dogs.
Cardiovascular responses to graded reductions in hindlimb perfusion in exercising dogs.
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运动犬后肢灌注逐渐减少的心血管反应。
DOI：
10.1152/ajpheart.1983.245.3.h481
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发表时间：
1983
期刊：
影响因子：
--
通讯作者：
Rowell,LB
中科院分区：
文献类型：
--
作者：
Wyss,CR;Ardell,JL;Scher,AM;Rowell,LB
在六只训练以每小时2、4和6英里的速度跑步的狗中，我们通过压迫末端主动脉引起后肢灌注的分级减少。我们的目标是检查后肢灌注[主动脉末流量（TAQ）和股动脉压（FP）]与心血管反应[主动脉压（AP）、心率和升主动脉流量（CO）]之间的关系。TAQ和FP的小幅降低导致心动过缓，CO小幅降低，AP小幅增加。TAQ和FP的进一步降低导致心动过速、CO增加和AP大幅增加。FP每下降1 mmHg，AP就会上升约1 mmHg。在所有速度下的反应都是相似的，但随着工作负荷的增加，需要FP和TAQ的较小降低才能引起升压反应（例如，在6mph时，我们不能证明TAQ和AP之间的非线性关系）。在低工作负荷下，对运动的心血管反应最有可能是由运动肌肉的反馈以外的信号设定的，因为后肢灌注的大幅减少不会引起显着的心血管反应。在中到高的工作负荷或肌肉灌注受到限制的情况下，来自肌肉的代谢反馈可能在心血管对运动的反应中发挥作用。
In six dogs trained to run at 2, 4, and 6 mph, we caused graded reductions in hindlimb perfusion by compressing the terminal aorta. Our goal was to examine the relationship between hindlimb perfusion [terminal aortic flow (TAQ) and femoral arterial pressure (FP)] and cardiovascular responses [aortic pressure (AP), heart rate, and ascending aortic flow (CO)]. Small reductions in TAQ and FP produced bradycardia, small decreases in CO, and small increases in AP. Further reductions in TAQ and FP produced tachycardia, increased CO, and large increases in AP. AP rose by about 1 mmHg for each 1-mmHg fall in FP. The response was similar at all speeds, but as work load increased it required smaller reductions in FP and TAQ to cause a pressor response (e.g., at 6 mph we could not demonstrate a nonlinear relationship between TAQ and AP). At low work loads the cardiovascular responses to exercise were most likely set by signals other than feedback from exercising muscle because substantial reductions in hindlimb perfusion caused no significant cardiovascular responses. At moderate-to-high work loads or where muscle perfusion is restricted, metabolic feedback from muscle may play a role in cardiovascular responses to exercise.