Research paper
Sympathetic outflow to muscles during vasovagal syncope

https://doi.org/10.1016/0165-1838(82)90001-7Get rights and content

Abstract

Sympathetic vasoconstrictor impulses were recorded with microelectrodes in peroneal muscle nerve fascicles during vasovagal syncope in two subjects. After a preceding period of increased nerve activity, onset of syncope was associated with bradycardia and sudden cessation of sympathetic outflow. The findings provide direct evidence that neurally mediated muscular vasodilation occurring during syncope is due to inhibition of vasoconstrictor impulses.

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