ABSTRACT
Objective To investigate the mecbanism of safflor injection treating myocardial contusion following thoracic impact.Methods Thirty healthy Japan big-ear rabbits were randomly assigned to the myocardial contusion control group (control group,n =15) and safflor injection group (safflor group,n =15).The rabbits with severe myocardial contusion were induced by BIM-Ⅱ Horizontal Bioimpact Machine.Blood samples were taken from common carotid artery of both groups to measure the levels of plasma thromboxance A2 (TXA2) and prostaglandin I2 ( PGI2 ) at 10 minutes before impact and at t0 minutes,30 minutes,1,3,6,12 and 24 hours after impact.Rabbits were dissected to observe the gross and micropathological changes of the hern at 24 hours after impact.Results The control group showed a distinct falling of plasma PGI2 concentration and a significant increase of plasma TXA2 concentration in the early period after severe myocardial contusion.The morphological observation revealed severe myocardial tissue injury as well.However,the safflor group showed insignificant variation pertaining to the reduction of plasma PGI2 concentration and increase of plasma TXA2 concentration,but obvious alleviation of myocardial tissue injury,as compared with the control group.Meanwhile,the ratio of TXB2 to 6- Ketoprostaglandin Fla (6-Keto-PGFla) in the safflor group was lower than that of the control group (P ＜0.05).Conclusion Safflor injection has therapeutic effect on myocardial contusion by elevating the concentration of plasma PGI2 and decreasing the concentration of plasma TXA2 in the early period after severe myocardial contusion.