Correlation between postischemic vasodilation of the arteria brachialis and of the postischemic hyperemia in the adjacent microvascular bed.
BACKGROUND
Endothelial cells secrete different mediators depending on biochemical and/or biophysical conditions, which can lead to vasodilation or vasoconstriction, respectively. Impaired endothelial responsiveness to specific vasodilator stimuli has been used as a surrogate marker of cardiovascular risk. Multiple methods allow testing endothelial responses in both microvessels and conduit arteries, but it is still unclear whether there is a relationship in endothelial function between these two different vascular beds.


METHODS
In order to examine, whether such macrocirculatory data might correlate with data obtained in the supplied microvessels, a parallel investigation in the brachial artery (BA) and the supplied nailfold capillaries was performed. The duration and amplitude of the postischemic hyperemia (stasis in the vasculature of the left arm using a blood pressure cuff for 3 minutes) were measured (ultrasound technique) and simultaneously the amplitude and duration of the postischemic hyperemia in ipsilateral nailfold capillaries (intravital capillaroscopy).


RESULTS
There was absolutely no correlation between the duration (n = 153, r = 0.076, p = 0.3493) of the diameter increase in the BA and in ipsilateral nailfold capillaries.


CONCLUSIONS
The regulation of the cutaneous microcirculation did not follow diameter changes of the conduit artery (BA) but seems to be dominated by the precapillary arterioles.
Center for Biomaterial Development and Berlin-Brandenburg Center for Regenerative Therapies, Institute of Polymer Research, Helmholtz Zentrum Geesthacht, Teltow, Germany. friedrich.jung@hzg.de
F
F
Jung
B
B
Leithäuser
R
R
Sternitzky
C
C
Mrowietz
G
G
Pindur
D000328:Adult; D000368:Aged; D001132:Arm / Q000098:blood supply*; D001783:Blood Flow Velocity; D001916:Brachial Artery / Q000473:pathology / Q000503:physiopathology*; D002196:Capillaries / Q000473:pathology / Q000503:physiopathology; D003327:Coronary Disease / Q000503:physiopathology; D004730:Endothelium, Vascular / Q000503:physiopathology; D005260:Female; D006801:Humans; D006940:Hyperemia / Q000473:pathology / Q000503:physiopathology*; D007511:Ischemia / Q000473:pathology / Q000503:physiopathology*; D008297:Male; D018715:Microscopy, Video; D055806:Microvessels / Q000502:physiology*; D008875:Middle Aged; D009262:Nails / Q000098:blood supply; D015424:Reperfusion; D014111:Tourniquets; D014664:Vasodilation / Q000502:physiology*; D055815:Young Adult