The Role Of Hemoglobin, Its Degradations And Heme Oxygenase Inhibitor In Brain Edema Of ICH

Objectives1.To study the relationship between autohemoglobin and brain edema in ICH;2.To study the role of heine oxygenase inhibitor in brain edema of ICH in order to provide theoretical foundation for the treatment of brain edema;Materials and Methods1.The 44 Sprague-Dawley rats were devided into 3 groups randomly,group A(A₁&A₂),group B(B₁&B₂)and group C(C_&C₂);2.Saline(group A & group B)and ZnPP(group C)were injected separately into the abdominal cavity 2 hours earlier before the operation;3.The rats were anesthetized with an intraperitoneal injection and then fixed on a stereotactic frame.A microsyringe was inserted stereotaxically into the right caudate nucleus of the rat(coordinates:0.2mm anterior,5.5mm ventral,and 3mm lateral to the bregma),saline(group A)and autohemoglobin liquor(group B & group C)were given separately to the caudate nucleus of the rats;4.Behavioral test was performed at 6,12 and 24 hours by Berderson Scale;5.At 22 hours post-operation,the saline(group A₁.B₁&C₁)and EB solution(group A₂,B₂ & C₂)were given through vena caudalis separately,which cycled in vivo body for 2 hours;at 24 hours post-operation,the COHb level of the vena caudalis (group A₁.B₁I& C₁)was examined and then the rats were killed by decapitation,the brain were removed to quantitate the water content and observed by the method of HE staining;for group A₂,B₂ and C₂,the rats were opened cavitas thoracis and perfused the saline into the heart,examined the BBB permeability.Results1.The marks of group C defective neurologic function were lower than group B (P＜0.05);2.The COHb level of group B was higer than group A(P＜0.05),and group C was lower than group B(P＜0.05); 3.The gestalt form of the brain:in group B,the right cerebral hemisphere swelled,the gyri extended,the sulci became shallow;the change of group C was slighter,in group A the bilateral hemispheres were approximately symmetric.HE staining and observing by Light-microscope:in group B,the brain edema and neural injury could be observed,inflammatory cells transmigrated,the nervous tissues were loose,nerve cells and colloidal cells swelled,and in cell space there were vacuoles in different sizes and the cell space increased,the cell ballooning degeneration and necrosis could be observed,the changes of group C were slighter.There were no obvious pathological changes in group A;4.The BBB permeability of group B was was significantly higher than group A (P＜0.05),and group C was significantly lower than group C(P＜0.05);5.The brain water content of group B was significantly higher than group A and C (P＜0.05).Conclusions1.The blood was taken from angulus oculi medialis,the autohemoglobin was injected stereotaxically into the right caudate nuclus of the rat,the way of establishing the model of ICH was simple,duplicate,reliable and operative during the experiment;2.Injecting autohemoglobin into brain tissue can cause brain edema which confirms the notion that the neurotoxic effect of hemoglobin to the brain tissue in ICH;3.The brain water content/BBB permeability and COHb decreased after ZnPP was injected into abdominal cavity,which demonstrated that ZnPP can inhibit hemoglobin from breakdowning and abate brain edema caused by hemoglobin;4.The role of the HO- 1 expression in the formation of delayed brain edema which is caused by the erythrocyte is important Interfering the crest-time of the expression of HO-1 may relieve the destruction of the BBB permeability and the brain injured caused by the out burst releasing of Hb metabolites.