Urotensin II in patients with chronic heart failure.
BACKGROUND
Human Urotensin II (hU-II) is the most potent vasoconstrictor known to date. HU-II receptors are predominant in the human heart and arterial vessels, suggesting hU-II to be of importance as a cardiovascular mediator.


METHODS
We studied 32 consecutive patients (60+/-12 years) with chronic heart failure (CHF) and 10 control subjects (54+/-12 years, n.s.) with cardiopulmonary exercise testing. Blood samples for the measurement of plasma hU-II and big-endothelin-1 (big-ET1) were obtained at rest and at peak exercise.


RESULTS
Peak VO(2) was significantly higher in controls than in CHF patients (19.8+/-3.8 vs. 14.7+/-3.6 ml min(-1) kg(-1), P<0.001). Big-ET1 levels were increased in CHF compared to controls at rest (2.8+/-1.8 vs. 1.7+/-0.1 fmol/ml, P<0.01) and at peak exercise (2.7+/-1.7 vs. 1.6+/-0.2 fmol/ml, P<0.005). HU-II concentrations were comparable in patients with CHF and controls at rest (2990+/-1104 vs. 3290+/-508 pg/ml, n.s.) and peak exercise (3063+/-1185 vs. 3213+/-1188 pg/ml, n.s.). Resting hU-II levels demonstrated no correlation with peak VO(2) in controls or CHF patients.


CONCLUSIONS
The measurement of circulating plasma levels of hU-II does not seem to be very helpful in studying the effects of hU-II in human cardiovascular regulation. A local paracrine or autocrine mediator effect of hU-II in CHF is possible.
Krüger
Stefan
S
Medical Clinic I and the Institute of Clinical Chemistry and Pathobiochemistry, University Hospital, University of Technology, Aachen, Germany.
Graf
Jürgen
J
Kunz
Dagmar
D
Stickel
Tina
T
Merx
Marc W
MW
Hanrath
Peter
P
Janssens
Uwe
U
D000368:Aged; D019332:Endothelin-1 / Q000097:blood; D015444:Exercise / Q000502:physiology; D005260:Female; D006333:Heart Failure / Q000097:blood*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010101:Oxygen Consumption; D013318:Stroke Volume; D014579:Urotensins / Q000097:blood*
D019332:Endothelin-1; D014579:Urotensins; C029677:urotensin II