Treadmill exercise-induced release of endothelin-1 in patients with peripheral arterial occlusive disease at Fontaine stage IIb.
BACKGROUND
Endothelin-1 (ET-1) is an endothelial vasoconstrictor mitogenic peptide which is thought to be a marker of endothelial damage and a potential participant in the pathophysiological processes of the development of atherosclerotic lesions and disease states associated with vasoconstriction and vasospasm.


METHODS
To investigate the endothelin-1 release in response to dynamic exercise in patients with peripheral arterial occlusive disease (PAOD), plasma concentrations were determined by radioimmunoassay in 16 patients (14 men, 2 women, mean age 56.2 +/- 8.1 years) with peripheral arterial occlusive disease at Fontaine stage IIb and in 10 control subjects (8 men, 2 women, mean age 58.1 +/- 7.2 years) in normal health during treadmill testing (slope 5%, speed 3 km/hr). Blood samples were collected at rest from an antecubital vein, at the onset of claudication pain, and 10 minutes after exercise.


RESULTS
Mean plasma endothelin-concentrations during the stress test increased significantly in the patients with arterial disease, rising from basal values of 4.4 +/- 0.6 pmol/L to values of 8.9 +/- 0.7 pmol/L at the end of the test (p < 0.0001), whereas it did not change significantly in control subjects (rising from 2.6 +/- 0.4 pmol/L to 2.7 +/- 0.5 pmol/L). Further, plasma endothelin- in the patients with arterial disease was at all times higher than in the control subjects (p < 0.0001).


CONCLUSIONS
In conclusion, this study shows that in patients with peripheral arterial occlusive disease, plasma endothelin-1 increases after treadmill exercise performed until claudication pain supervenes. Raised endothelin-1 could be a marker of ischaemic acute endothelial damage and/or could contribute to increase the vascular resistance in ischaemic limbs of these patients during dynamic exercise by promoting arterial/arteriolar vasoconstriction or vasospasm.
Mangiafico
R A
RA
Institute of Clinica Medica L Condorelli, University of Catania, Italy. robct@iol.it
Malatino
L S
LS
Spada
R S
RS
Santonocito
M
M
Messina
R
R
Dell'Arte
S
S
Attinà
T
T
D001157:Arterial Occlusive Diseases / Q000097:blood* / Q000175:diagnosis / Q000503:physiopathology; D015415:Biomarkers / Q000097:blood; D001783:Blood Flow Velocity / Q000502:physiology; D001794:Blood Pressure / Q000502:physiology; D019332:Endothelin-1 / Q000097:blood*; D015444:Exercise / Q000502:physiology*; D005080:Exercise Test; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012720:Severity of Illness Index; D018616:Ultrasonography, Doppler, Duplex; D014655:Vascular Resistance / Q000502:physiology
D015415:Biomarkers; D019332:Endothelin-1