TY - JOUR
T1 - Endothelium-dependent vasodilation in well-developed coronary collateral vessels
AU - Dulas, Daniel
AU - Altman, John D.
AU - Hirata-Dulas, Cheryl
AU - Bache, Robert J.
PY - 1996
Y1 - 1996
N2 - We examined endothelium-dependent vasodilator responses in well- developed coronary collateral vessels. Collateral vessels and size matched normal epicardial coronary arteries were isolated from canine hearts 6 months after a hollow plug had been introduced into the left anterior descending coronary artery (LAD) to stimulate collateral vessel growth. Vessel segments were isolated and studied in organ chambers. After preconstriction with prostaglandin F(2α), (PGF(2α)) responses to the endothelium-dependent vasodilators, acetylcholine (ACh), substance P, and bradykinin (BK), as well as the endothelium-independent vasodilator nitroglycerin (NTG), were measured. The maximum relaxation to ACh was greater in collateral vessels (129 ± 3.6% of the preconstricted tension) than in normal vessels (110 ± 6.2%, p < 0.001), although the EC50 value for ACh was not significantly different between collateral and normal vessels. Collateral vessels demonstrated sensitivity to BK similar to that of normal vessels, but the maximal vasodilation achieved was greater in collaterals (138 ± 4.6% of preconstricted tension) than in normal vessels (108 ± 5.0%, p < 0.05). Both substance P and NTG produced dose-related relaxation that was similar in collateral vessels and normal arteries. These findings demonstrate that endolethelium-dependent relaxation is intact in well developed coronary collateral vessels.
AB - We examined endothelium-dependent vasodilator responses in well- developed coronary collateral vessels. Collateral vessels and size matched normal epicardial coronary arteries were isolated from canine hearts 6 months after a hollow plug had been introduced into the left anterior descending coronary artery (LAD) to stimulate collateral vessel growth. Vessel segments were isolated and studied in organ chambers. After preconstriction with prostaglandin F(2α), (PGF(2α)) responses to the endothelium-dependent vasodilators, acetylcholine (ACh), substance P, and bradykinin (BK), as well as the endothelium-independent vasodilator nitroglycerin (NTG), were measured. The maximum relaxation to ACh was greater in collateral vessels (129 ± 3.6% of the preconstricted tension) than in normal vessels (110 ± 6.2%, p < 0.001), although the EC50 value for ACh was not significantly different between collateral and normal vessels. Collateral vessels demonstrated sensitivity to BK similar to that of normal vessels, but the maximal vasodilation achieved was greater in collaterals (138 ± 4.6% of preconstricted tension) than in normal vessels (108 ± 5.0%, p < 0.05). Both substance P and NTG produced dose-related relaxation that was similar in collateral vessels and normal arteries. These findings demonstrate that endolethelium-dependent relaxation is intact in well developed coronary collateral vessels.
KW - Acetylcholine
KW - Bradykinin
KW - Coronary occlusion
KW - Nitroglycerin
KW - Substance P
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U2 - 10.1097/00005344-199610000-00002
DO - 10.1097/00005344-199610000-00002
M3 - Article
C2 - 8891871
AN - SCOPUS:0029738918
SN - 0160-2446
VL - 28
SP - 488
EP - 493
JO - Journal of Cardiovascular Pharmacology
JF - Journal of Cardiovascular Pharmacology
IS - 4
ER -