Effects of dexmedetomidine on the degree of myocardial ischemia-reperfusion injury, oxidative stress and TLR4/NF-kappa B signaling pathway in rats

To investigate the effects of dexmedetomidine on the degree of myocardial ischemia-reperfusion injury (MIRI), oxidative stress and Toll-like receptor 4 (TLR4)/nuclear factor kappa B (NF-kappa B) signaling pathway in rats. Thirty-six adult healthy SD rats were randomly divided into experimental group, injury group and control group by random number table. Dexmedetomidine, 0.9% sodium chloride solution and pre-treatment with 0.9% sodium chloride solution for 1 hour were given respectively. CK-MB, cTn-I, NT-proBNP and LDH levels in the experimental group and the injury group were significantly higher than those in the control group; SOD activity in the experimental group and the injury group were significantly superior to that in the control group; GSH contents in the experimental group and the injury group were significantly less than that in the control group; The MDA contents of the experimental group and the injury group was significantly greater than that of the control group; the TLR4 and NF-kappa B protein expression levels of the experimental group and the injury group were significantly higher than that of the control group (all P<0.05). Dexmedetomidine can effectively reduce myocardial injury caused by myocardial ischemia-reperfusion (I/R), reduce the expression of TLR4 and NF-kappa B, negatively regulate its signaling pathway, alleviate oxidative stress response.