AJP - Heart and Circulatory Physiology, Vol 250, Issue 5 765-H768, Copyright © 1986 by American Physiological Society
Periodic cutaneous blood flow during postocclusive reactive hyperemia
J. K. Wilkin
Forearm cutaneous blood flow was monitored continuously by laser Doppler
velocimetry in 10 normal human subjects before, during, and after external
brachial artery occlusion for 6 min duration. During the reactive hyperemic
response, the cutaneous blood flow exhibited rhythmic oscillatory activity.
The amplitude of the oscillations was maximum 30 s postocclusion.
Thereafter, the amplitude of the oscillations declined until cutaneous
blood flow returned to control values. The mean (+/- SEM) period for the
oscillations was 9.26 +/- 0.30 s. Bilateral forearm sites were examined
simultaneously in eight studies and demonstrated a progressive loss of
synchronicity. Nine additional studies were performed in which two forearm
sites only 1.8 cm apart demonstrated a progressive loss of synchronicity
resulting from different periodicities of microcirculatory flow patterns.
These oscillations in cutaneous blood flow, which occur during
postocclusive reactive hyperemia as a normal physiological phenomenon, are
not synchronous in adjacent areas of skin. The data suggest an origin of
the oscillations in the cutaneous vasculature that is either unrelated to
sympathetic vasoconstrictor influences or is due to nonuniform cutaneous
sympathetic excitation.
