What question did this study set out to answer?

To determine whether local autoregulation or reflex neurohumoral control predominates in regulating hindlimb blood flow during different intensities of treadmill exercise.

February 1, 1991AJP Heart and Circulatory Physiology

Reflex versus autoregulatory control of hindlimb blood flow during treadmill exercise in dogs

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Authors

LKLauren G. KochUniversity of Toledo DSD. M. StrickMayo Clinic SBSteven L. BrittonGeneral / Preventive / Lipids

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Implication

Neurohumoral override of autoregulation at low exercise intensity in dogs; leaves open balance during human limb hypoperfusion.

Key Points

To determine whether local autoregulation or reflex neurohumoral control predominates in regulating hindlimb blood flow during different intensities of treadmill exercise.
Studied nine dogs performing treadmill exercise at low intensity (3.0 km/h, 0% grade) and high intensity (5.5 km/h, 14% grade).
Imposed a 10% reduction in mean arterial pressure for 25 minutes using a carotid gravity reservoir while measuring hindlimb blood flow with an external iliac Doppler probe.
Assessed mechanistic pathways using autonomic ganglionic blockade with hexamethonium and adenosine receptor antagonism with aminophylline.
A 10 ± 2% decrease in mean arterial pressure caused hindlimb blood flow to drop by 25 ± 2% during low-intensity exercise (closed-loop gain = -1.6 ± 0.4), but only by 10 ± 2% during high-intensity exercise (closed-loop gain = -0.06 ± 0.2).
Autonomic ganglionic blockade with hexamethonium shifted the closed-loop gain during low-intensity exercise to 0.07 ± 0.2.
Adenosine receptor antagonism with aminophylline decreased the closed-loop gain during high-intensity exercise to -0.57 ± 0.3.

Cite This Study

Koch et al. (1991) studied this question.

synapsesocial.com/papers/6a7226eb5671bbf00bc3058f https://doi.org/10.1152/ajpheart.1991.260.2.h436

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Reflex versus autoregulatory control of hindlimb blood flow during treadmill exercise in dogs

Discussion

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Implication

Key Points

Cite This Study

Reflex versus autoregulatory control of hindlimb blood flow during treadmill exercise in dogs

Discussion

Member takes

Implication

Key Points

Cite This Study

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