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Updated: Jun 5, 2026

Standardized Rat Coronary Ring Preparation and Real-Time Recording of Dynamic Tension Changes Along Vessel Diameter
Published on: June 16, 2022
[Effects of proanthocyanidins on contractile activity of aortic smooth muscle and platelet aggregation in
Xiao-Yu Zhang1, Wen-Guang Li, Tian-Zhen Zheng
1Department of Physiology, College of Basic Medicine, Lanzhou University, Lanzhou 730000, China.
Aim:
To study effects of proanthocyanidins (PA) on contractile activity of isolated aortic smooth muscle in rats and rabbit platelet aggregation.
Methods:
Isolated rat aortic muscle rings were adopted to observe the effects of PA on their contraction induced by noradrenaline (NA) or KCl, and their tensions were recorded by BL-310 experimental system of biological function. Rabbit platelet aggregation induced by arachidonic acid (AA), adenosine diphosphate (ADP), and collagen (Coll) was assayed by turbidimetry.
Results:
PA could significantly inhibit the contraction induced by NA (10(-6) mol/L), low the concentration-response curves of NA and the maximal response on the endothelium-intact or endothelium-denuded aortic rings. But PA couldn't relax the aortic rings precontracted with KCl and had no influence on rabbit platelet aggregation induced by AA, ADP, and Coll.
Conclusion:
PA can inhibit the contraction induced by NA but not by KCl on isolated rat aortic rings. It also has no influence on rabbit platelet aggregation.
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