Effect of coriaria lactone-activated astrocyte-conditioned medium on the cerebral TNF-α of normal rats

Abstract

To explore the effect of coriaria lactone (CL)-activated astrocyte-conditioned medium on the cerebral TNF-α of normal rats, the CL-activated astrocyte-conditioned medium (ACM) was injected into the lateral ventricle of SD rats. The rats were observed for behavioral changes, and the changes of the expression of TNF-α in the cerebral cortex and hippocampus were immunohistochemically examined by employing SP method. TNF-α level was assessed by means of radioimmunoassay in homogenate of cerebral cortex and hippocampus as well as cerebrospinal fluid. Seizure episodes were observed in ACM group 30 min after the ACM injection, but they were not observed in the control group. Immunohistochemical detection showed that the immunoreaction of TNF-α in hippocampus and cerebral cortex of rats were stronger than that of the control group 4 h after the ACM injection (P<0.05). In this group, the concentrations of TNF-α in homogenate of cerebral cortex and hippocampus and cerebrospinal fluid were higher than those of the control group (P<0.05). It is suggested that the ACM activated by CL can enhance the expression of TNF-α in normal rats, and is related to epileptogenesis.

Keywords

ACM / astrocyte / seizure / TNF-α

References

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