Prostaglandin F 2α decreases the affinity of epidermal growth factor receptors in Swiss mouse 3T3 cells via protein kinase C activation

Abstract

Prostaglandin F 2α (PGF 2α) selectively decreases the binding of 125I-labelled epidermal growth factor ([ 125I]EGF) to intact Swiss 3T3 cells. Scatchard analysis reveals that PGF 2α decreases the number of high-affinity EGF binding sites without changing the total number of receptors. Prostaglandins E 1 (PGE 1), E 2 (PGE 2 or F 2β (PGF 2β) do not alter the EGF binding to these cells and do not enhance the PGF 2α effect. R-59022 and R-59949, two diacylglycerol kinase inhibitors, enhance the inhibitory effect of PGF 2α, whereas down-modulation of protein kinase C (PKC) abolishes the effect. These results indicate that PGF 2α, decreases EGF binding in Swiss 3T3 cells via PKC activation.