Abstract
Acetylcholine (ACh) induced concentration-dependent relaxations of rabbit aortic strips precontracted with noradrenaline. The relaxations were abolished if the endothelium of the strips was disrupted. Three different antioxidants (butylated hydroxytoluene, dithiothreitol and alpha-tocopherol) reversed the endothelium-dependent vasodilation in a concentration-dependent manner. However, the antioxidant ascorbic acid did not alter the vasodilatation. The hydroxylated eicosatetraenoic acids 5-HETE, 12-HETE, 15-HETE and 5,12-diHETE had no effect on aortic strips under basal or induced tension. These results suggest, that (non-cyclo-oxygenase) oxidation processes, insensitive to the action of ascorbic acid, represent a crucial step in the endothelium-dependent dilatation of rabbit aorta by ACh. The hydroxylated fatty acids tested are unlikely to mediate this relaxation.
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Selected References
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- Capdevila J., Chacos N., Werringloer J., Prough R. A., Estabrook R. W. Liver microsomal cytochrome P-450 and the oxidative metabolism of arachidonic acid. Proc Natl Acad Sci U S A. 1981 Sep;78(9):5362–5366. doi: 10.1073/pnas.78.9.5362. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Chacos N., Falck J. R., Wixtrom C., Capdevila J. Novel epoxides formed during the liver cytochrome P-450 oxidation of arachidonic acid. Biochem Biophys Res Commun. 1982 Feb 11;104(3):916–922. doi: 10.1016/0006-291x(82)91336-5. [DOI] [PubMed] [Google Scholar]
- De Mey J. G., Claeys M., Vanhoutte P. M. Endothelium-dependent inhibitory effects of acetylcholine, adenosine triphosphate, thrombin and arachidonic acid in the canine femoral artery. J Pharmacol Exp Ther. 1982 Jul;222(1):166–173. [PubMed] [Google Scholar]
- De Mey J. G., Vanhoutte P. M. Role of the intima in cholinergic and purinergic relaxation of isolated canine femoral arteries. J Physiol. 1981 Jul;316:347–355. doi: 10.1113/jphysiol.1981.sp013792. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Duniec Z., Robak J., Gryglewski R. Antioxidant properties of some chemicals vs their influence on cyclooxygenase and lipoxidase activities. Biochem Pharmacol. 1983 Jul 15;32(14):2283–2286. doi: 10.1016/0006-2952(83)90239-3. [DOI] [PubMed] [Google Scholar]
- Furchgott R. F., Zawadzki J. V. The obligatory role of endothelial cells in the relaxation of arterial smooth muscle by acetylcholine. Nature. 1980 Nov 27;288(5789):373–376. doi: 10.1038/288373a0. [DOI] [PubMed] [Google Scholar]
- Förstermann U., Hertting G., Neufang B. The importance of endogenous prostaglandins other than prostacyclin, for the modulation of contractility of some rabbit blood vessels. Br J Pharmacol. 1984 Apr;81(4):623–630. doi: 10.1111/j.1476-5381.1984.tb16127.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Morrison A. R., Pascoe N. Metabolism of arachidonate through NADPH-dependent oxygenase of renal cortex. Proc Natl Acad Sci U S A. 1981 Dec;78(12):7375–7378. doi: 10.1073/pnas.78.12.7375. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Singer H. A., Peach M. J. Endothelium-dependent relaxation of rabbit aorta. II. Inhibition of relaxation stimulated by methacholine and A23187 with antagonists of arachidonic acid metabolism. J Pharmacol Exp Ther. 1983 Sep;226(3):796–801. [PubMed] [Google Scholar]
- Wills E. D. Lipid peroxide formation in microsomes. General considerations. Biochem J. 1969 Jun;113(2):315–324. doi: 10.1042/bj1130315. [DOI] [PMC free article] [PubMed] [Google Scholar]