Bradykinin-induced venodilation is not different in blacks.
OBJECTIVE
The aim of this study was to determine whether young, normotensive blacks who have been recently demonstrated to have a venodilator response to isoprenaline decreased compared with whites, also have an decreased vasodilatory response to bradykinin.


METHODS
Eleven black and 11 white subjects were studied. Full dose-response curves to bradykinin (dosing range 0.5-500 ng min-1) were generated in hand veins preconstricted with phenylephrine (dosing range 20-6800 ng min-1).


RESULTS
The groups had a similar maximal response to bradykinin (57.6 +/- 32.2% vs 67.8 +/- 49.3%, P = NS 95% confidence interval for the difference (CI): -47.3, 26.8). Also, the log of the dose that produced half maximal response to bradykinin was similar for the two groups (0.89 +/- 0.58 vs 0.78 +/- 0.61 ng min-1, P = NS, 95% CI: -0.42, 0.64). There was no difference between the two groups in the log dose of phenylephrine necessary to produce 80% constriction of the hand vein.


CONCLUSIONS
Diminished vasodilatory response to endothelium-derived relaxing factor (EDRF) does not seem to be associated with the increased prevalence of hypertension in blacks.
Vajo
Z
Z
Department of Medicine, Maricopa Medical Center, Phoenix, Arizona 85008, USA.
McDonald
M
M
Takahashi
B
B
Zafar
H
H
Srivathsan
K
K
Dachman
W D
WD
D000328:Adult; D044383:Black People; D001920:Bradykinin / Q000494:pharmacology*; D005260:Female; D006225:Hand / Q000098:blood supply; D006801:Humans; D008297:Male; D010656:Phenylephrine / Q000494:pharmacology; D014664:Vasodilation; D014665:Vasodilator Agents / Q000494:pharmacology*; D014680:Veins / Q000187:drug effects* / Q000502:physiology; D044465:White People
D014665:Vasodilator Agents; D010656:Phenylephrine; D001920:Bradykinin