The Experimental Study Of Protection Of SMC On The Early Myocardium Damage Postburn In Rats

Objective To observe the alteration of serum Cardiac troponin-I (cTnI) and tumor necrosis factor-alpha (TNF-a) in the early stage of severe scalded Wistar rats, and to investigate the protection of salvia miltiorrhiza compound( SMC) from the early myocardium damage of severe scalded rals . Methods Seventy-two cases of Wistar rat were randomly divided into three groups: the control(n=8), the recovery(n=32) and the treatment(n=32), and in the later two groups a scald burn comprising 30 percent of the total body surface area full-thickness were established. The activity of serum myocardial enzymes (LDH, CK, CK-MB) and the content of cTnl and TNF-a were detected in 3,6,12 and 24 hours after the burns, as well as the water content in myocardium. The morphologic changes were observed by light and electrical microscope. The indexes above were analyzed to acknowledge the variations in three groups with SPSS solfware. Results (1) In the fluid resuscitation groups, LDH, CK, cTnl and TNF-a went up 3 hours after bums, CK-MB went up remarkably 6 hours after the scalding, all attaining the top at 12 hours postburn, in cTnl increasing about 106 times of control value at 12 hours postburn, and still higher than the control 24 hours after scalding. Water contain in the myocardium were apparently higher than the control. (2) In the treatment groups, the indexs above had the same trends as the recovery. But comparing with the fluid resuscitation, cTnl and TNF-a were much lower at 3,6,12 and 24 hours, LDH in the treatment was much lower at 6,12 hours after the scalding, CK and the water contain were lower 6 hours, CK-MB was lower in 12 and 24 hours being lower in 12 hours. (3) A series of histological and ultrastractural changes in themyocardium were found at 3 and 6 hours postburn, the above changes attained the worst in 24 hours. Comparing with the fluid resuscitation groups, the pathological changes were obviously alleviated in the treatment groups. Conclusions ( 1) cTnI is a reliable index for the early myocardial damage in serious scalding, and more sensitive than LDH, CK, CK-MB. TNF- plays a role in the occurring and progress of early myocardial damage. (2) SMC protects the myocardium of seriously scalded rats in early stage. The possible mechanism may be to relieve the production and releasing of the inflammatory factors and lighten the myocardial damage.