The Study Of Protective Effect And Molecular Mechanisms Of ShenFu Injectionon On Cardiomyocyte Injuried By Hypoxia/Reperfusion

Background and purpose With extensive clinical practice of many kinds of technology for vessel recanalization, myocardial ischemia-reperfusion injury (IRI) have already received the attention of the masses of scientific researchers. Exploration about mechanisms and therapeutical measurement of IRI has currently become one of focuses of medical research. In the present study, to demonstrate the cardioprotective effect and mechanisms of ShenFu Injection (SFI) on cardiomyocte injuried by Hypoxia/Reoxygenation (H/R), the H/R model of cultured cardiomyocte of SD rat in vitro was established, and viability and vitality of injuried cardiac myocyte, apoptosis ratio of cells injuried by H/R, concentration of cytoplasmic free calcium([Ca²⁺]_i), expression of Heat Shock Protein70 (HSP70) and variation of activity of Nuclear Factor- κ B(NF- κ B) were determined. Methods Cardiomyoctes were divided into different six groups:control group, H/R group, H/R+SFI₁ group, H/R+SFI₂ group, H/R+SFI₃ group, H/R+ Verapamil group. Cell viability of every group was counted by utilization of trypan blue.Cell vitality of every group was measured with MTT chromatometry.The percentage of apoptotic cells and expression of HSP70 were determined by flow cytometry. Concentration of cytoplasmic freecalcium was determined by dual wavelength spectrofluorometer, The change of activity of NF- k B was measured with immunohistochemistry method. Result (l)The percentage of viability and vitality of cardiomyocyte was low in H/R group(P<0.01 vs control group).SFI could show increase in viability and vitality of cardiomyocytes(P<0.05 or PO.01 vs H/R).(2)The apoptotic ratio of cardiomyocytes was obviously raised with H/R (9.77±0.80, PO.01 vs control).SFI could exert a concentration-dependent inhibition in cardiomyocytes appptosis (400 u l/ml,7.30±0.56;200 u l/ml,6.17±0.40;100u l/ml,5.17±0.45; P<0.01 vs H/R).(3)The concentration of cytoplasmic free calcium was distinctly raised in H/R group (956.26±76.01, PO.01 vs control).SFI could produce inhibition in concentration of cytoplasmic free calcium (400 u I/ml, 881. 29 ±65. 86, 200 u I/ml, 767. 33 + 94. 31; 100 U I/ml, 617. 98+191. 64,P<0.05 vs H/R).(4)The expression of HSP70 was improved in all groups except for Control group. But it was more significant with SFI(400 ii I/ml, 23.90 + 0.20; 200 u I/ml, 37. 33 + 0. 25;100u I/ml, 39.57 + 0.49; PO.01 vs H/R).(5)NF -k B lay in cytoplasm and kept a inactivity situation in control group.It was activated in cardiomyocytes injuried by H/R and transferred into nucleolus.SFI could inhibit NF- k B activation. Conclusion SFI can significantly augment viability and vitality of cardiomyocytes injuried by hypoxia-reoxygenation, reduce apoptotic ratio of cells during hypoxia-reoxygenation.SFI bring cardioprotective effect on injuried cardiomyocytes through the dcrease of cytoplasmic free calcium,the increase of protective HSP70, the depression of NF - k B activity.