The Expression Of Calcium Sensing Receptor During Myocardial Damage By Spinal Cord Injury In Rats

Objection :Expression of calcium sensing receptor(CaSR) during myocardial damage by high-level spinal cord injury(SCI) in rats to observe the mechanism of myocardial damage by spinal cord injury in rats.Methods:The experimental model was established by high-level spinal cord injury in rats.SD rats were randomly divided into 5 groups:sham group,spinal cord injury 6h,12h,24h,48h groups(A,B,C,D group).The level of plasma creatine kinase(CK), MB isoenzyme of creatine kinase(CK-MB) and troponinâ… (cTnI)were measured.CaSR mRNA expression was detected by fluorescence quantitative PCR. CaSR protein expression was detected by Western blot. The change of ultrastructure in the myocardium of rats was observed by electron microscopy.Result: In 4?injury groups, the values of cardiac enzymes were much higher than that of sham group(p<0.05) and the expression of CaSR mRNA and protein were significantly upregulated(p<0.05). Troponinâ… and CK-MB reaching peak at 12 hours(p<0.05),CK reching peak at 24 hours(p<0.05). CaSR mRNA and protien reaching peak at 24 hours(p<0.05).Uhrastructural examination of the myocardial tissue demonstrated that there were apoptosis of myocardial cells and vacuolation of mitochondria after injury.Conclusions: After SCI the level of cTnI,CK,CK-MB short time significantly increased in rats plasma,clue to myocardial damage ,it could not come back to the level of before injury even in 48 h;after SCI myocardial apoptosis could be found under electron microscope,it reach peak in 12h;the excessive expression of CaSR mRNA and protien might be one mechanism of myocardial damage after SCI.