Expression And Significance Of S100B Protein And MBP In Brains And Serum Of Young Rats With Epilepsy Induced By Pentylenetetrazol

[Objective]By investigating the changes of S100B protein and MBP in serum and different brains of young rats with epilepsy induced by pentylenetetrazol(PTZ),and to evaluate the effect of epileptogenesis upon brain damage.[ Methods]Sixty male 4-5 weeks SD young rats of clean grade,inbred strain,were randomly divided into experimental groups and control group.The experimental groups were injected intraperitoneally (IP) with PTZ (50mg/kg).And the control group (Group A,n=10) was injected IP with same normal saline.The experiment groups were divided into seizured groups and without seizure group (Group B,n=9) which was decapitated immediately.Groups of seizures were sacrificed at T=0h (Group C,n=10),6h (Group D,n=10),24h (GroupE,n=10) and 72h (Group F,n=10) after developing seizures . We randomly choiced 2 rats from every group for immunohistochemistry study . Blood samples were collected before sacrificed.Enzyme-linked immunosorbent assay (ELISA) was used to evaluate the levels of S100B protein and MBP in mesencephalon,hippocampus,frontal cortex and serum.And by envison two steps immunohistochemistry to observe the expression of S100B protein and MBP in the hippocampus of rats.[Resusltfs]1The models of young rats with epilepsy induced by pentylenetetrazol were successful.2 Levels of S100B protein in different brains and serum were dynamic changes after seizure;Levels of S100B protein in hippocampus,frontal lobe,and serum were all increased at 6h,getting the highest at 24h after seizure,and compared control group, there were statiscally significance(P<0.05 or P<0.001),back to the normal levels in 72h;Level of S100B protein in mesencephalon was increased after 24h after seizures, and compared control group, there was statiscally significance(P<0.001),back to control level after 72h after seizures,and it indicated that neuron cells of hippocampus and frontal lobe of rats were damaged earlier than those of mesencephalon of rats.Levels of S100B protein of different brains and serum in groups B and C showed no statiscally significance compared control group (P>0.05);3 Levels of MBP in different brains and serum were dynamic changes after seizure; Levels of MBP in hippocampus,frontal lobe and serum were all increased at 24h,getting the highest in the 72h after seizure,and compared control group,there were statiscally significance(P<0.05 or P<0.001);Level of MBP in mesencephalon was increased after 72h,and compared control group, there was statiscally significance(P<0.001),and it also indicated that neuron cells of hippocampus and frontal lobe of rats were damaged earlier than those of mesencephalon of rats.Levels of MBP of different brains and serum in groups B and C and D showed no statiscally significance compared control group(P>0.05);4 Levels of S100B protein in hippocampus of rats were significantly higher than those of in serum,and it showed positive correlations between them,and they were r=0.88,P<0.05;Levels of MBP in hippocampus of rats were also significantly higher than those of in serum,and it showed positive correlations between them,and they were r=0.82,P<0.05;5 The expression of S100B protein immunoreactivity of young rats hippocampus was increased at 6h,getting the highest at 24h after seizure;6 The expression of MBP immunoreactivity of young rats hippocampus was increased at 24h,getting the highest at 72h after seizure.[Conclusion ]1 The model of young rats of epilepsy induced by PTZ were ideal generalized tonic-colonic model.2 The significant increase of S100B protein in serum and brains of PTZ-induced young rats showed the damage degree of glial cell.3 The significant increase of MBP in serum and brains of PTZ-induced young rats suggested the damage of myelin fabric after seizure. 4 The significant increase of S100B protein and MBP immunoreactivity in hippocampus of PTZ-induced young rats confirmed the damage of glial cells and myelin fabric which were caused by epilepsy.5 Both levels of S100B protein and MBP in hippocampus of rats significantly higher than those of in serum,and it showed positive correlations between them,which indicates that increased S100B protein and MBP after seizure may come through the damaged blood brain barrier to the peripheral serum.6 The changes of S100B protein and MBP were correlative to the duration of seizure.And both of S100B protein and MBP may be regarded as the sensitive and specific brain damage biomarkers after seizure.