PROTEIN-KINASE-C IS INVOLVED IN CHOLECYSTOKININ OCTAPEPTIDE-INDUCED PROLIFERATIVE ACTION IN RAT GLIOMA C-6 CELLS

Chotecystoknin octapeptide (CCK-8) has been shown to stimulate DNA syn thesis in rat glioma C-6 cells by activation of CCKB type receptors. H owever, the signalling pathways contributing to this proliferative act ion in C-6 cells have not been investigated thus far. This study demon strated that stimulation of rat glioma C-6 cells with CCK-8S resulted in activation of protein kinase C isozymes beta I, beta II, gamma and zeta. The participation of protein kinase C in the CCK-8S-induced effe ct on C-6 cell growth was demonstrated by measurement of [H-3]thymidin e incorporation and estimation of cell number. The data indicate that CCK-8S stimulates growth in rat glioma C-6 cells by a protein kinase C -dependent mechanism.