TY - JOUR
T1 - Modulation of endothelium-dependent responses by chronic alterations of blood flow
AU - Miller, V. M.
AU - Aarhus, L. L.
AU - Vanhoutte, P. M.
PY - 1986
Y1 - 1986
N2 - To determine whether the blood flow and O2 tension to which a blood vessel is chronically exposed could modulate endothelium-dependent responses, these parameters were altered in the dog either by causing partial occlusion of the femoral artery or by creating a fistula between the femoral artery and vein. Blood flow was reduced by 75% in the clamped artery; mean arterial pressure was unchanged. In the vessels proximal to the fistula, blood flow was elevated and O2 tensions were similar in the vein and artery. After 6 wk the femoral arteries and veins were excised, and their endothelium-dependent responses were studied in vitro. The endothelium-dependent relaxations to acetylcholine, adenosine diphosphate, and α2-adrenergic stimulation were augmented in fistula-operated compared with sham-operated arteries. The responses to these agents in the clamp-operated vessels were not different from those of the sham-operated ones. Relaxation to arachidonic acid in the arteries showed an inverse relationship to blood flow. In the veins proximal to the fistula, the endothelium-dependent relaxations to acetylcholine were augmented and an endothelium-dependent relaxation to α2-adrenergic stimulation was present; only a contractile response was observed in veins from the sham-operated limb in response to the latter. These studies suggest a pattern of increased endothelium-dependent relaxation in vessels exposed to chronically elevated blood flow.
AB - To determine whether the blood flow and O2 tension to which a blood vessel is chronically exposed could modulate endothelium-dependent responses, these parameters were altered in the dog either by causing partial occlusion of the femoral artery or by creating a fistula between the femoral artery and vein. Blood flow was reduced by 75% in the clamped artery; mean arterial pressure was unchanged. In the vessels proximal to the fistula, blood flow was elevated and O2 tensions were similar in the vein and artery. After 6 wk the femoral arteries and veins were excised, and their endothelium-dependent responses were studied in vitro. The endothelium-dependent relaxations to acetylcholine, adenosine diphosphate, and α2-adrenergic stimulation were augmented in fistula-operated compared with sham-operated arteries. The responses to these agents in the clamp-operated vessels were not different from those of the sham-operated ones. Relaxation to arachidonic acid in the arteries showed an inverse relationship to blood flow. In the veins proximal to the fistula, the endothelium-dependent relaxations to acetylcholine were augmented and an endothelium-dependent relaxation to α2-adrenergic stimulation was present; only a contractile response was observed in veins from the sham-operated limb in response to the latter. These studies suggest a pattern of increased endothelium-dependent relaxation in vessels exposed to chronically elevated blood flow.
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U2 - 10.1152/ajpheart.1986.251.3.h520
DO - 10.1152/ajpheart.1986.251.3.h520
M3 - Article
C2 - 3752266
AN - SCOPUS:0023037175
SN - 0363-6135
VL - 251
SP - H520-H527
JO - American Journal of Physiology - Heart and Circulatory Physiology
JF - American Journal of Physiology - Heart and Circulatory Physiology
IS - 3 (20/3)
ER -