Jia Guo-Dong, Long Chao-Liang, Liu Guo-Shu
Institute of Pharmacology and Toxicology, Academy of Military Medical Sciences, Beijing 100850, China.
Zhongguo Ying Yong Sheng Li Xue Za Zhi. 2002 Aug;18(3):252-6.
To compare the differences of pharmacological characteristics of the endothelial target for acetylcholine (ETA) between rat aorta and tail artery.
Differences 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.
ACh-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.
It 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.
比较大鼠主动脉和尾动脉中乙酰胆碱内皮靶点（ETA）的药理学特性差异。
使用离体大鼠尾动脉螺旋条和主动脉环，研究乙酰胆碱（ACh：10⁻⁸ - 10⁻⁴mol/L）诱导的内皮依赖性舒张差异，从而观察小动脉中ETA的药理学特性。
在大鼠尾动脉条和用氯化钾（60 mmol/L）预收缩的主动脉环中均观察到ACh诱导的内皮依赖性舒张呈浓度依赖性。在尾动脉中，这种效应被L-硝基精氨酸甲酯（L-NAME：10⁻⁴mol/L）或亚甲蓝（MB：10⁻⁵mol/L）以及吲哚美辛（Indo：10⁻⁴mol/L）部分阻断，但在主动脉中，它被L-NAME或MB完全阻断。
大动脉和小动脉中ETA的药理学特性不同。一种非NO和非PGI2的舒张因子与一氧化氮（NO）和前列环素（PGI2）一起介导小动脉中ACh诱导的内皮依赖性血管舒张，但NO可能是大动脉中主要的内皮血管舒张物质。
