Related Experiment Video
Updated: Jul 11, 2026

Two-photon Imaging of Intracellular Ca2+ Handling and Nitric Oxide Production in Endothelial and Smooth Muscle Cells of an Isolated Rat Aorta
Published on: June 10, 2015
Luteolin induces vasorelaxion in rat thoracic aorta via calcium and potassium channels
Huidi Jiang1, Qiang Xia, Xiaoxia Wang
1College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, China. hdjiang@zju.edu.cn
Abstract:
The aims of the present study were to investigate the vasoactive effects of luteolin and its mechanisms of action on the rat thoracic aorta. Luteolin (4.5-36 micromol/L) caused a concentration-dependent relaxation of endothelium-intact or endothelium-denuded aortic rings precontracted with phenylephrine (PE, 10(-6) mol/L) or a high level of K+ (6 x 10(-2) mol/L). Luteolin induced a shift of the PE concentration-response curve to the right and downward. L-NAME and propranolol did not influence the vascular effect of luteolin. However, 5-hydroxydecanoate, tetraethylammonium, BaCl2 and 4-aminopyridine significantly attenuated the vasorelaxant effect of luteolin. In Ca2+ -free medium, medium with graded concentrations of Ca2+, or K+ -free solution, luteolin reduced PE-induced contraction. It is concluded that luteolin induces endothelium-independent relaxation in rat thoracic aorta. The mechanism involves the inhibition of sarcolemmal Ca2+ channels, release from intracellular Ca2+ stores and activation of K+ channels.
More Related Videos
09:47Measurement of Endothelium-Dependent Vasorelaxation in the Mouse Thoracic Aorta Using Tensometric Small Volume Chamber Myography
Published on: August 12, 2022
07:53Standardized Rat Coronary Ring Preparation and Real-Time Recording of Dynamic Tension Changes Along Vessel Diameter
Published on: June 16, 2022
Related Concept Videos
Nitric Oxide Signaling Pathway
Antihypertensive Drugs: Action of Calcium Channel Blockers
Antihypertensive Drugs: Angiotensin-Converting Enzyme Inhibitors
Antihypertensive Drugs: Angiotensin II Receptor Blockers
Antihypertensive Drugs: Vasodilators
Antianginal Drugs: Calcium Channel Blockers and Ranolazine
CCBs, a diverse class that includes dihydropyridines (nifedipine) and diphenylalkylamines (verapamil and diltiazem), exert their effect by blocking calcium channels in cardiac and smooth muscle cells. This...