Study On The Expression Of ADM And Its Receptor After HIBD In Neonatal Rats

ObjectiveIn our experiment HIBD model was established,use RT-PCR technology to explore the expressions of the ADM and its receptor mRNA in different times of brain cortex.Thus expound further that formates the influence secreted on ADM and receptor while HIBD pathology forms,may be provide a novel approach in the diagnoses,treatment and syntesis of HIE in clinical practice.MethodsNeonatal 7-day-old Wistar rats were under a middle anterior neck incision.The left common carotid artery was isolated and ligated,then the pups were exposed to hypoxic environment (8%O₂) for 2 hours.One hundand animals were randomly assigned to the sham-operation group,HIBD different time points group.Eight were measured the expression of ADMmRNA and its receptors mRNA in cortex at different time points by the reverse-transcription PCR.Two by henmatoxylin-eosin (HE).Results1. Histological studyThere was no obvious sign of neuronal damage and with cells of apparently normal appearance in the brain tissue in control group and 0h after HIBD.There were degenerated neurons were scatered in the cortex and hippocampus in 2h to 4h after HIBD.In 6h to 8h after HIBD,there were laminal and patchy distributionof neuronal necrosis and edema were apparent in the cortex and hippocampus.In 10h to 12h after HIBD,the neuronal necrosis severer than the 8h after HIBD.Pyramidal cells showed some disorders in the hippocampus and no proliferation of glial cells appeared.In 24h to 48h after HIBD:Neuronal necrosis is severer.Pyramidal cells showed disorders in the hippocampus and proliferation of glial cells appeared.2. Results(l):Expression of ADM mRNA:The expression of ADM mRNA was observed both in control and HIBD groups.The level of ADM mRNA in ischemic cortex began to increase within 4h(P < 0.01 vs control),peaked at 8h after HIBD(P< O.Olvs other groups,except vs lOh) and decreased after this,especially at 48h after HIBD,but the mRNA for ADM was still higher than the normal level(But P>0.05 vs control).(2): Expression of ADMR mRNA:The expression of ADMR mRNA was observed both in control and HIBDgroups.The level of ADM mRNA in ischemic cortex began to increase within 2h(P < 0.05 vs control),peaked at 8h after HIBD(P< O.Olvs other groups) and decreased after this.But the mRNA for ADMR was still higher than the normal level(P>0.05 vs control).(3):Expression of CRLR mRNA:The expression of CRLR mRNA was observed both in control and HIBDgroups.The level of ADM mRNA in ischemic cortex began to increase within 2h(P < O.Olvs control,peaked at 8h after HIBD(P< O.Olvs other groups) and decreased after this.But the mRNA for ADM was still higher than the normal level(P < 0.05 vs control).(4): Expression of RAMPs mRNA?:The expression of RAMP1 mRNA was observed both in control and...