Effects Of Methylene Blue On Heart And Lung Function Of Septic Rats In Different Periods

Objective: To study the effects of methylene blue(MB) on heart and lung function ofseptic rats in different periods and investigate the mechanism of MB. Methods: Makingmodel of sepsis using the cecal ligation and puncture(CLP). Using different length ofcecal ligation and recovery modeling,to esplore the appropriate model for thisexperiment.After the modeling,10mg/kg methylene blue were given at early(10h) andlate(20h).10-12h later,blood pressure,arterial blood gas parameters and serum level of NOwere measured.Taking heart and lung tissues for histopathological and iNOS protein weredetected by immunohistochemistry. Results: The survival rate of rats were affected bydifferent modeling methods.MAP and SPO2decline over time in both early group and lategroup,the late group were significantly lower(P<0.05).MB can improve MAP significantlyin later group (P<0.05).MB has no effect on blood gas analysis,the index was no statisticaldifference(P>0.05).The serum level of NO was increased after modeling,MB had no effecton serum level of NO in the early group,MB can significantly reduce serum level of NO inthe late group.After the modeling,heart and lung tissue have significant histopathologicalchanges,the treatment of MB has little effect on the degree of tissue damage.there havedifferent iNOS protein expression in different periods of sepsis,the effect of MB are alsodifferent. Conclusions: The length of cecal ligation and recovery level can affect thesurvival rate of septic rats.MB can significantly improve hemodynamic in late septicrats,MB had no effect on blood gas values. the treatment of MB has little effect on thedegree of tissue damage.there have different iNOS protein expression in different periodsof sepsis,...