Bao Yi-Min, Liu Ai-Hua, Zhang Zhi-Xiong
Department of Physiology, Shanghai University of Traditional Chinese Medicine, Shanghai.
Zhongguo Zhong Xi Yi Jie He Za Zhi. 2010 Oct;30(10):1056-60.
To investigate the changes in contents of cycloxygenase-2 (COX-2) and its downstream effectors in rat's myocardial ischemia/reperfusion (I/R) model and observe the effects of precondition with GBE50 (Ginkgo biloba extract 50) and Salviae miltiorrhizae (SM) on them.
Rat's I/R model was established by 30-min left anterior descending coronary artery occlusion followed with 60-min reperfusion. Animals were divided into the model control group, the sham-operated group and the tested groups (received 1-week precondition with GBE50 and SM respectively via intragastric infusion before modeling). COX-2 mRNA expression in myocardium was detected by real-time PCR; contents of thromboxane B2 (TXB2) and 6-keto-prostaglandin F1alpha (6-keto-PGF1alpha) were measured by radioimmunoassay.
The mRNA expression of COX-2 in the model group was obviously higher than that in the sham-operated group (P < 0.001), while that in the tested groups was down-regulated significantly (P < 0.01), and the content of TXB2 as well as the ratio of TXB2/PGF1alpha was reduced significantly (P < 0.05). Besides, SM also showed the up-regulation effect on 6-keto-PGF1alpha content in myocardium (P < 0.05).
COX-2 affects the myocardium through thromboxane A2 and prostacyclin after I/R; both GBE50 and SM can inhibit the production of COX-2, but they may act in different paths.
研究大鼠心肌缺血/再灌注（I/R）模型中环氧化酶-2（COX-2）及其下游效应分子含量的变化，并观察银杏叶提取物50（GBE50）和丹参（SM）预处理对其的影响。
通过结扎左冠状动脉前降支30分钟后再灌注60分钟建立大鼠I/R模型。动物分为模型对照组、假手术组和试验组（建模前分别通过灌胃给予GBE50和SM进行1周预处理）。采用实时定量PCR检测心肌中COX-2 mRNA表达；采用放射免疫分析法测定血栓素B2（TXB2）和6-酮-前列腺素F1α（6-keto-PGF1α）含量。
模型组COX-2 mRNA表达明显高于假手术组（P < 0.001），而试验组COX-2 mRNA表达明显下调（P < 0.01），TXB2含量及TXB2/PGF1α比值明显降低（P < 0.05）。此外，SM还可使心肌中6-keto-PGF1α含量上调（P < 0.05）。
I/R后COX-2通过血栓素A2和前列环素影响心肌；GBE50和SM均可抑制COX-2的产生，但作用途径可能不同。
