Protein expressions of S100B and calcitonin gene related peptide and pathological changes of the hippocampus in rats with kainic acid-induced epilepsy / 中华神经医学杂志

ABSTRACT

Objective To investigate the expressions of S100B and calcitonin gene related peptide (CGRP) and the pathologic alterations of the hippocampus in kainic acid (KA)-induced epileptic rats. Methods Male SD rats were randomly divided into control group (n=8) and model group (n=40).Animal models of temporal lobe epilepsy were established by intracerebroventricular injection of KA; the same volume of saline was injected into the rats in the control group. Hippocampal tissues within various phases after seizures (6, 12, 24 and 72 h, and 24 h after the success of model making) were performed Nissl staining, Timm staining and immunohistochemical staining. The expressions of S100B and CGRP were observed, and the pathologic alterations of the hippocampal neurons and glial cells were studied.Results All rat models were successfully induced with epileptic seizures. Nissl staining showed that pyknotic neuronal necrosis appeared in the CA3 area of the hippocampus in the model group with cell body atrophy and disappearance of Nissl bodies 1 week after the injection. Timm staining showed that brown particles showed stripped distribution in the CA3 area of the hippocampus and some brown particles in the molecular layer of fascia dentate. Immunohistochemical staining indicated that significant neurons lost and gliosis appeared after seizures with abundant expressions of S100B and CGRP.Conclusion KA-induced epileptic rats express abundant S100B and CGRP and appear such pathological changes as disappearance of Nissl bodies and mossy fiber sprouting, indicating that both S100B and CGRP participate in the onset of epilepsy.