Altered PLCß-1 expression in the gerbil hippocampal complex following spontaneous seizure.

ABSTRACT

Although the phospholipase C (PLC)ß-1 isoform is associated with spontaneous seizure and distinctively expressed in the telencephalon, the distribution of PLCß-1 expression in the epileptic gerbil hippocampus remains controversial. Therefore, we determined whether PLCß-1 is associated with spontaneous seizure in an animal model of genetic epilepsy. In the present study, PLCß-1 immunoreactivity was down-regulated in seizure-sensitive (SS) gerbils more than in seizure-resistant (SR) gerbils. The expression of PLCß-1 within calretinin (CR)- positive neurons was rarely detected within the dentate hilar region of SS gerbils. PLCß-1 immunoreactivity in the hippocampus was significantly elevated as compared to that in pre-seizure SS gerbil 3 h post-ictal. These findings suggest that alterations in PLCß-1 immunoreactivity in the SS gerbil hippocampus may be closely related to the epileptic state of the gerbil brain and transiently elevated PLCß-1 protein levels following seizure episodes. Such alterations may be compensatory responses in the SS gerbil hippocampus.