Reduced expression of Phospholipase C beta in hippocampal interneuron during pilocarpine induced status epilepticus in mice.

We investigated localization of Phospholipase C beta (PLCβ1 and PLCβ4) in laminaes of dorsal hippocampus and different subtypes of hippocampal interneurons in normal Kunming mouse, and their progressive changes during pilocarpine induced status epilepticus (SE) by quantitative immunohistochemistry and real time PCR. PLCβ1 was observed in the pyramidal layer of CA1-3 area, hilus of the dentate gyrus, whereas PLCβ4 was mainly expressed in calcium binding protein positive interneurons, i.e. calbindin, calretinin, parvalbumin positive interneurons in the strata oriens, radiatum of the CA area and hilus of the dentate gyrus. During pilocarpine induced SE, a temporary down-regulation of PLCβ4 in the interneurons of CA area at SE 30min, and a progressive reduction of PLCβ1/PLCβ4 in dentate hilar cells were demonstrated. These findings confirm and extend the regional specific distribution of PLCβ1 and PLCβ4 immunoreactivity in mouse hippocampus, and suggest that PLCβ1 and PLCβ4 may play an important role in maintenance of the status epilepticus.