The Effect Of Remifentanil For Controlled Hypotension Level On Brain Matrix INOSmRNA During Partial Hepatic Ischemia/reperfusion Brain Injury In Rat

Objective: To investigate the effects of Remifentanil for controlled hypotension level on inducible nitric oxide synthase(iNOS)mRNA during partial hepatic ischemia-reperfusion brain injury in rats and mechanism involved.Methods A total of 32 healthy SD rats weighing 280-320 g were randomly divided into 4 groups(n=8 each):sham operation group(group S): the hilum of liver was isolated but not clamped;partial hepatic ischemia-reperfusion(I/R): the left and median lobe of liver was occluded for60 min followed by reperfusion;Remifentanil group(Rem)and sodium nirtoprusside group(SNP)were respectively given the intravenous of Remifentanil or sodium nirtoprussideand esmolol combinantion induce for 5 minutes in front of open hepatic vein injection,to implement controlling step-down,10 min reperfusion period to maintain the MAP in 70 mm Hg.Rats were scarified at 24 h of reperfusion after 1h hepatic ischemia.The rats in group S were also killed.The brains were removed for determination of NO content(by nitrate reductase assay),SOD activity(by xanthine oxidase method),MDA content(by colorimetric method),and iNOS mRNA expression(by RT-PCR).Results Compared with group S,the MDA,NO and iNOS mRNA were significantly increased in groups I/R?Rem and SNP(P<0.05);SOD content relative were reduced(P < 0.05).Compared with I/R,the MDA,NO and iNOS mRNA were reduced in Rem and SNP(P<0.05);SOD content relative were increased(P<0.05).Compared with SNP,the MDA,NO and i NOS mRNA were reduced in Rem(P<0.05);SOD content relative were increased(P<0.05).Conclusion Remifentanil for controlled hypotension level can reduce the brain injury caused by liver ischemia reperfusion,whose mechanism may be related to lower levels of NO,the inhibition of iNOS mRNA expression,ete.