Abstract:

Abstract:Objective
To observe the changes of the orexin-B cells and their nerve fibers in the rat epilepsy model at different time points and elucidate their roles in the seizure.Methods Seizures were induced by intraperitoneal injection of kainic acid(KA),then the changes of the orexin-B immunoreactive cells and nerve fibers were detected by immunohistochemistry at 8 h,1 d, 3 d,7 d and chronic relapsing time after the termination of epilepsy respectively.Results The orexin-B immunoreactive cells mainly distributed in the hypothalamus and perifornical nuclei,not cerebral cortex and other brain tissues,but the suspicious positive cells were  detected in the hippocampus.The orexin-B immunoreactive nerve fibers  distributed widely.The orexin-B immunoreactive cells were decreased slightly in the first and  resumed，then were decreased and resumed again.And the cell count of orexin-B was significantly  decreased in 7 d group compared with other groups(P<0.05).The change trend of cell count of orexin-B was opposite to the one of nerve fibers. Conclusion The  orexin-B immunoreactive cells and the immunoreactive fibers of the orexin-B have changes in the process of  the seizures,it  shows that they may involved in the regulation of epilepsy.And it can help to control seizures by increasing the  concentration of orexin-B.

Key words: epilepsy, orexin-B, rats, kainic acid