[Effect of precondition with GBE50 and Salviae miltionrrhizae on cycloxygenase-2 and its downstream effectors contents in ischemia/reperfusion myocardium].
OBJECTIVE
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.


METHODS
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.


RESULTS
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).


CONCLUSIONS
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.
Department of Physiology, Shanghai University of Traditional Chinese Medicine, Shanghai.
Yi-Min
YM
Bao
Ai-Hua
AH
Liu
Zhi-Xiong
ZX
Zhang
D015121:6-Ketoprostaglandin F1 alpha / Q000378:metabolism; D000818:Animals; D051546:Cyclooxygenase 2 / Q000235:genetics / Q000378:metabolism*; D004365:Drugs, Chinese Herbal / Q000627:therapeutic use*; D020441:Ginkgo biloba / Q000737:chemistry*; D019157:Ischemic Preconditioning, Myocardial / Q000379:methods*; D008297:Male; D017202:Myocardial Ischemia / Q000503:physiopathology; D015428:Myocardial Reperfusion Injury / Q000378:metabolism* / Q000473:pathology; D009206:Myocardium / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D027561:Salvia miltiorrhiza / Q000737:chemistry*; D013929:Thromboxane B2 / Q000378:metabolism
D004365:Drugs, Chinese Herbal; D012333:RNA, Messenger; D013929:Thromboxane B2; D015121:6-Ketoprostaglandin F1 alpha; D051546:Cyclooxygenase 2; C489691:Ptgs2 protein, rat