Effect of Chinese Herbal Medicine “Saiko-keishi-to” on Intracellular Calcium and Protein Behavior During Pentylenetetrazole-Induced Bursting Activity in Snail Neurons

Abstract

The Chinese herbal medicine “Saiko-Keishi-To” (SK), which is a mixture of nine crude drugs, shows a dramatic anticonvulsant effect in some difficult cases of epilepsy which had long been unsuccessfully treated by established anticonvulsant drugs. The anticonvulsant mechanism of SK was investigated from the viewpoint of intracellular calcium and protein behavior during bursting activity, which is characteristic of seizure discharge. SK clearly inhibited the intracellular calcium shift toward the cell membrane as well as the calcium binding state change near the cell membrane during bursting activity induced by pentylenetetrazole (PTZ). SK also inhibited the intracellular protein changes during PTZ-induced bursting activity together with the incorporation of calcium into these proteins. These findings suggest that the mechanism of anticonvulsant action of SK is closely related to pathologically induced intracellular calcium and protein changes during seizure activity.