Topic
Vasoconstriction
About: Vasoconstriction is a research topic. Over the lifetime, 12987 publications have been published within this topic receiving 433886 citations. The topic is also known as: GO:0042310 & negative regulation of blood vessel size.
Papers published on a yearly basis
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Papers
TL;DR: The preliminary findings suggest that the abnormal vascular response to acetylcholine may represent a defect in endothelial vasodilator function, and may be important in the pathogenesis of coronary vasospasm.
Abstract: Acetylcholine is believed to dilate normal blood vessels by promoting the release of a vasorelaxant substance from the endothelium (endothelium-derived relaxing factor). By contrast, if the endothelium is removed experimentally, acetylcholine constricts blood vessels. We tested the hypothesis that muscarinic cholinergic vasodilation is impaired in coronary atherosclerosis. Graded concentrations of acetylcholine and, for comparison, the nonendothelial-dependent vasodilator nitroglycerin were infused into the left anterior descending artery of eight patients with advanced coronary stenoses (greater than 50 percent narrowing), four subjects with angiographically normal coronary arteries, and six patients with mild coronary atherosclerosis (less than 20 percent narrowing). Vascular responses were evaluated by quantitative angiography. In several segments each of four normal coronary arteries, acetylcholine caused a dose-dependent dilation from a control diameter of 1.94 +/- 0.16 mm to 2.16 +/- 0.15 mm with the maximal acetylcholine dose (P less than 0.01). In contrast, all eight of the arteries with advanced stenoses showed dose-dependent constriction, from 1.05 +/- 0.05 to 0.32 +/- 0.16 mm at the highest concentration of acetylcholine (P less than 0.01), with temporary occlusion in five. Five of six vessels with minimal disease also constricted in response to acetylcholine. All vessels dilated in response to nitroglycerin, however. We conclude that paradoxical vasoconstriction induced by acetylcholine occurs early as well as late in the course of coronary atherosclerosis. Our preliminary findings suggest that the abnormal vascular response to acetylcholine may represent a defect in endothelial vasodilator function, and may be important in the pathogenesis of coronary vasospasm.
2,603 citations
TL;DR: Endothelium-dependent relaxation of blood vessels is produced by a large number of agents (e.g., acetylcholine, ATP and ADP, substance P, bradykinin, histamine, thrombin, serotonin). With some agents, relaxation may be limited to certain species and/or blood vessels as mentioned in this paper.
Abstract: Endothelium-dependent relaxation of blood vessels is produced by a large number of agents (e.g., acetylcholine, ATP and ADP, substance P, bradykinin, histamine, thrombin, serotonin). With some agents, relaxation may be limited to certain species and/or blood vessels. Relaxation results from release of a very labile non-prostanoid endothelium-derived relaxing factor (EDRF) or factors. EDRF stimulates guanylate cyclase of the vascular smooth muscle, with the resulting increase in cyclic GMP activating relaxation. EDRF is rapidly inactivated by hemoglobin and superoxide. There is strong evidence that EDRF from many blood vessels and from cultured endothelial cells is nitric oxide (NO) and that its precursor is L-arginine. There is evidence for other relaxing factors, including an endothelium-derived hyperpolarizing factor in some vessels. Flow-induced shear stress also stimulates EDRF release. Endothelium-dependent relaxation occurs in resistance vessels as well as in larger arteries, and is generally more pronounced in arteries than veins. EDRF also inhibits platelet aggregation and adhesion to the blood vessel wall. Endothelium-derived contracting factors appear to be responsible for endothelium-dependent contractions produced by arachidonic acid and hypoxia in isolated systemic vessels and by certain agents and by rapid stretch in isolated cerebral vessels. In all such experiments, the endothelium-derived contracting factor appears to be some product or by-product of cyclooxygenase activity. Recently, endothelial cells in culture have been found to synthesize a peptide, endothelin, which is an extremely potent vasoconstrictor. The possible physiological roles and pathophysiological significance of endothelium-derived relaxing and contracting factors are briefly discussed.
2,020 citations
TL;DR: It is demonstrated that neuronal activity and the neurotransmitter glutamate evoke the release of messengers that dilate capillaries by actively relaxing pericytes, which are major regulators of cerebral blood flow and initiators of functional imaging signals.
Abstract: Increases in brain blood flow, evoked by neuronal activity, power neural computation and form the basis of BOLD (blood-oxygen-level-dependent) functional imaging. Whether blood flow is controlled solely by arteriole smooth muscle, or also by capillary pericytes, is controversial. We demonstrate that neuronal activity and the neurotransmitter glutamate evoke the release of messengers that dilate capillaries by actively relaxing pericytes. Dilation is mediated by prostaglandin E2, but requires nitric oxide release to suppress vasoconstricting 20-HETE synthesis. In vivo, when sensory input increases blood flow, capillaries dilate before arterioles and are estimated to produce 84% of the blood flow increase. In pathology, ischaemia evokes capillary constriction by pericytes. We show that this is followed by pericyte death in rigor, which may irreversibly constrict capillaries and damage the blood-brain barrier. Thus, pericytes are major regulators of cerebral blood flow and initiators of functional imaging signals. Prevention of pericyte constriction and death may reduce the long-lasting blood flow decrease that damages neurons after stroke.
1,722 citations
TL;DR: Pulmonary arterial hypertension has a multifactorial pathobiology and recent genetic and pathophysiologic studies have emphasized the relevance of several mediators in this condition, including prostacyclin, nitric oxide, ET-1, angiopoietin- 1, serotonin, cytokines, chemokines, and members of the transforming-growth-factor-beta superfamily.
1,622 citations
TL;DR: In this paper, the authors tested the hypothesis that the acetylcholine response relates to risk factors for coronary artery disease and found that coronary risk factors are associated with loss of endothelium-dependent vasodilation.
Abstract: In animals, acetylcholine dilates normal arteries and produces vasoconstriction in the presence of hypercholesterolemia, hypertension, or atherosclerosis, reflecting endothelial cell dysfunction. In patients with angiographically smooth coronary arteries, acetylcholine has been reported to produce both vasodilation and constriction. To test the hypothesis that the acetylcholine response relates to risk factors for coronary artery disease, acetylcholine 10(-8) to 10(-6) M was infused into the left anterior descending or circumflex coronary artery, and diameter changes were assessed with quantitative angiography in 34 patients with angiographically smooth coronary arteries. The acetylcholine response ranged from +37% (dilation) to -53% (constriction) at the peak acetylcholine dose. All coronary arteries dilated in response to nitroglycerin (26 +/- 17%), suggesting an abnormality of endothelial function in the patients with a constrictor response to acetylcholine. By multiple stepwise regression analysis, serum cholesterol (p less than 0.01), male gender (p less than 0.001), family history (p less than 0.05), age (p less than 0.05), cholesterol level (p less than 0.01), and total number of risk factors (p less than 0.0001) were independently associated with the acetylcholine response. Thus, coronary risk factors are associated with loss of endothelium-dependent vasodilation. The development of vasoconstriction is likely to be an abnormality of endothelial function that precedes atherosclerosis or an early marker of atherosclerosis not detectable by angiography.
1,281 citations
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Performance Metrics
| Year | Papers |
|---|---|
| 2025 | 72 |
| 2024 | 123 |
| 2023 | 188 |
| 2022 | 299 |
| 2021 | 156 |
| 2020 | 149 |