The Dynamic Expression And Correlation Between ENT1and ADK Mediated By Astrocytes In The Rats’Hippocampus Of TLE

Objective To observe the dynamic expression of ENT1and A.DK mediated by astrocytes in the rats’ hippocampus after pilocarpine-induced seizures, and to investigate their role in the process of epileptogenesis.Method84healthy male Sprague-Dawley (SD) rats were divided randomly into experimental group (n=60), control (NS) group (n=12) and normal group (n=12). The temporal lobe epilepsy model was established by intraperitoneal. injection of lithium and pilocarpine, while the controls were injected with equal dose of saline. The experimental rats were equally divided into5subgroups at time points2hours,1day,7days,15days and30days after status epileptics (SE). Each subgroup was subsequently divided into2panels (6rats in each panel) for the following tests respectively:①expression of ENT1and ADK protein in rats’ hippocampus by Western blot;②expression of ENT1and ADK protein in rats’ different region of the hippocampus (CA1area, CA3area, DG area) by immunohistochemistry and co-expression of astrocytes and ENT1, ADK in rats’ hippocampus by double immunofluorescence.Results1. The lithium-pilocarpine model of TLE:SE rate reached86.7%, total mortality rate was18.3%and the succeful rate was68.3%.2. The expression of ENT1protein in the hippocampus of experimental rats compared with the control rats:The expression of ENT1protein markedly downregulated on2h after SE(P<0.01), then it rebounded gradually yet but was still lower than normal on1d (P<0.01). Until7d, it reached the normal. On15d, it significantly upregulated and reached the peak on30d(P<0.01).3. The expression of ADK protein in the hippocampus of experimental rats compared with the control rats:The expression of ADK protein markedly downregulated on2h after SE(P<0.01), then it rebounded the normal on1d. It still upregulated and reached the peak on30d (P<0.01).4. The expression of ENT1and ADK were observed in different region of the rats’hippocampus (CA1area, CA3area, DG area) all the time and changed with the time of SE:they markedly downregulated on2h after SE (P <0.01), and then upregulated gradually.5. Astrocytes and ENT1, ADK co-expression was observed in CA1area of rats’ hippocampus. What’s more, the expression of them markedly downregulated on2h after SE (P<0.01), and then upregulated gradually with astrogliosis.Conclusion1.The expression of ENT1and ADK were downregulated in acute phase and upregulated in chronic phase in rats’ hippocampus of TLE, and the correlation between them was positive.2. Astrocytes regulate adenosine by altering the expression of ENT1and ADK which maybe one of the mechanisms in epilepsy.