Comparison of pharmacological characteristics of the endothelial target for acetylcholine between big artery and small artery.
- Author:
Guo-Dong JIA
1
;
Chao-Liang LONG
;
Guo-Shu LIU
Author Information
- Publication Type:Journal Article
- MeSH: Acetylcholine; pharmacology; Animals; Aorta; drug effects; Arteries; drug effects; Endothelium, Vascular; drug effects; physiology; In Vitro Techniques; Male; Rats; Rats, Wistar; Vasodilation; drug effects
- From: Chinese Journal of Applied Physiology 2002;18(3):252-256
- CountryChina
- Language:Chinese
-
Abstract:
AIMTo compare the differences of pharmacological characteristics of the endothelial target for acetylcholine (ETA) between rat aorta and tail artery.
METHODSDifferences in the endothelium-dependent relaxation induced by acetylcholine (ACh: 10(-8) - 10(-4) mol/L) were studied using isolated rat tail artery helical strips and aortic rings, so that the pharmacological characteristics of ETA in small artery can be observed.
RESULTSACh-induced endothelium-dependent relaxation was observed both in rat tail artery strips and in aortic rings precontracted with potassium chloride (60 mmol/L) in a concentration-dependent manner. In tail artery this effect was partially blocked by L-N(omega)-Nitro-arginine methyl ester (L-NAME: 10(-4) mol/L) or methylene blue (MB: 10(-5) mol/L), together with indomethacin (Indo: 10(-4) mol/L), but in aorta it was completely blocked by L-NAME or MB.
CONCLUSIONIt is different of the pharmacological characteristics of ETA between big artery and small artery. A non-NO and non-PGI2 relaxing factor, together with nitric oxide (NO) and prostacyclin (PGI2), mediates endothelium-dependent vasorelaxation induced by ACh in small artery, but NO may be the principal endothelial vasodilator substance in big artery.
