Experimental Studies On The Protective Effect Of Octreotide Againstischemia-reperfusion Injury On Rat Brain

Objective: 1.To investigate the protective effect and mechanism of Octreotide against ischemia-reperfusion injury on rat brain. 2. Octreotide experimental dose in 50 ug/kg and 75 ug/kg curative effect for protection of ischemia reperfusion injury in rats with indifference.Methods: With the establishment of MCAO cerebral ischemia-reperfusion models,16 male SD rats were randomly divided into sham operation group(S group,n=4), ischemia-reperfusion group(I/R group n=4), preconditioning group with low dose octreotide(OPC1 group,n=4)and preconditioning group with high dose octreotide(OPC2 group,n=4). The time of cerebral ischemia was 2 hours and time of reperfusion was 24 hours.SOD and MDA in serum were measured and the change of morphology of brain cells was observed.The Mean apoptotic cells of right brain was compared among groups by TUNEL.Results:At 2h after ischemia and 24 h after reperfusion,the levels of superoxide dismutase(SOD)and malondialdehyde(MDA) in I/R 、OCT-L and OCT-H groups were higher than that of S groups significantly(P<0.05);the levels of SOD and MDA in OCT-L and OCT-Hgroups were higher than that of I / R group significantly(P<0. 05).Whereas OCT-L and OCT-H groups show no significant difference in the levels of SOD and MDA(P>0.05).No apoptotic cell was observed in the S group and a very small amount of apoptotic cells were observed in cortex 24 hours postoperatively in OCT-L acnd OCT-H groups,however,ischemic regions in I/R group are strewn with apoptotic cells and piles of apoptotic cells, neurons mostly,can be observed in the margin.Compared with control groups,apoptotic cells in OCT-L acnd OCT-H groups are less significantly at 24 hours after ischemia-reperfusion(P<0. 05), whereas OCT-L and OCT-H groups show no significant difference in the amount of apoptotic cells(P>0.05).Conclusions:1.Octreotideof has obvious protective effect on the SD rat In ischemia-reperfusion injury.2.There is no significant difference in protection of brain cells during the ischemia-reperfusion between the OCT-L( OCT 50ug/kg) and OCT-H(OCT 75ug/kg) groups.