Stimulation of prostaglandin E2 production by phorbol esters and epidermal growth factor in porcine thyroid cells

Effects of phorbol esters and epidermal growth factor (EGF) on prostaglandin E2 production by cultured porcine thyroid cells were examined. Both phorbol 12-myristate 13-acetate (PMA) and EGF stimulated prostaglandin E2 production by the cells in dose related fashion. PMA stimulated prostaglandin E2 production over fifty-fold with the dose of 10(-7) M compared with control. EGF (10(-7) M) also stimulated it about ten-fold. The ED50 values of PMA and EGF were respectively around 1 X 10(-9) M and 5 X 10(-10) M. Thyroid stimulating hormone (TSH), however, did not stimulate prostaglandin E2 production from 1 to 24-h incubation. The release of radioactivity from [3H]-arachidonic acid prelabeled cells was also stimulated by PMA and EGF, but not by TSH. These results indicate that both PMA and EGF are potent stimulators of prostaglandin E2 production, associated with the activity to stimulate arachidonic acid release in porcine thyroid cells.