The Study On The Expression Of PGP And MRP1 In Rat's Epileptic Model Induced By Pentylenetetrazol

Objective: 1 To set up acute seizure model in rats induced by peritoneal injection ofpentylenetetrazol(PTZ); phenobarbital(PB) sodium was used to intervene the seizures. Thenthe seizures were observed; observe pathologic alteration of rat's brains. 2 To investigate ifthe expression of PGP was increased in brains of rats, when it happened, and whether it wasrelated to severity of seizures and the application of PB; 3 To investigate if the expresion ofMRP1 was increased in the rat's brains, when it happened, and whether it was related toseverity of seizures and the application of PB sodium.Methods: 1 The rat's acute epileptic model was induced by peritoneal injection of PTZ(40mg～60mg/kg) in PTZ group; In PB group including pre-PB and post-PB subgroups,phenobarbital sodium (40mg/kg) was pedtoneally injected 0.5 hour before and 10 minues afterPTZ respectively; normal saline(2ml/rat) was peritoneally injected in pseudo-model group; Inblank group rats were given nothing. To observe the occurrence of seizure or not, type ofseizure and the time of beginning and the duration of seizure in all rats. HE staining was usedfor rats' brain (coronal section through hippocampus). 2 The immunohistochemistry techniquewas applied to compare the expression of PGP in rats' brains (coronal section throughhippoeampus) of blank group, pseudo-model group, PTZ group and PB group after 6 hours,24hours, 3 days, 5 days and 7 days of seizures. To probe if the expression of PGP was increased,when it happened, and whether it was related to severity of seizures and the application of PBsodium. 3 The immunohistochemistry technique was applied to compare the expression ofMRP1 in rats' brains (coronal section through hippocampus) of blank group, pseudo-modelgroup, PTZ group and PB group after 6h, 24h, 3d, 5d and 7d of seizures. To probe if theexpression of MRP1 was increased in brains, when it happened, and whether it was related toseverity of seizures and the application of PB sodium.Results: 1 Peritoneal injection of PTZ could be used to set up acute epileptic model inrats. Seizures of rats in PB group were less severe and the time was shorter in PB group than in PTZ group; No seizures happened in the rats of blank group and pseudo-model group.Pathologic alteration was very prominent after seizures in rats' brains. 2 Expression of PGPwithin 7 days was increased in rats' brains of PTZ group, especially 24h after seizures;expression of PGP in rats' brains of PB group was comparatively low; expression of PGP inrats' brains of blank group and pseudo-model group was weak. PGP expression wassignificantly higher in PTZ group (6h,24h,3d,5d and 7d after seizures, P＜0.05) and in PBgroup (24h,3d,5d and 7d after seizures, P＜0.05) when compared with those in blank groupand pseudo-model group. PGP expression was significantly higher in PTZ group and post-PBgroup (P＜0.01) in comparison of that in pre-PB group. 3 Expression of MRP1 within 7 dayswas increased in rats' brains of PTZ group, especially 7d after seizures; Expression of MRP1in rats' brains of PB group was comparatively low; No expression of MRP1 was in rats' brainsof blank group and pseudo-model group. MRP1 expression was significantly higher in PTZgroup and pre-PB group(6h,24h,3d,5d and 7d after seizures, P＜0.05) and in post-PB group(24h,3d,5d and 7d after seizures, P＜0.05) when compared with blank group and pseudo-modelgroup. MRP1 expression was significantly higher in PTZ group(P＜0.01)when compared withPB group.Conclusions: 1 Peritoneal injection of PTZ can be used to set up acute seizure model inrats, similar to epileptic attack in mankinds; Pathologic alteration in rat's brain tisue of PTZgroup are more severe than those of blank group, pseudo- model group and PB group. 2 thehigh expression of PGP and MRP1 is caused by seizures in rats' brains; the level of expressionis related to severity of seizures,the duration of seizure and the administration of PB sodium;PB sodium impacts the expression of PGP and MRP1 by influencing seizures of rats.