The animal ether phospholipid platelet-activating factor stimulates acidification of the incubation medium by cultured soybean cells.

Addition of the animal ether phospholipid platelet-activating factor, 1-0-alkyl-2-acetyl-sn-glycero-3-phosphocholine, (PAF) stimulates medium acidification in cultured soybean (Glycine max L.) cells. The pH of the medium after 8-10 hours is on the average one pH unit lower than in controls. With fusicoccin an average pH difference of 1.7 units is reached. Phospholipids, glycerol, 1-oleyl-2-acetyl-sn-glycerol, 1-0-hexadecyl-sn-glycerol, and triolein at the same concentrations as PAF had no stimulatory effect on medium acidification. The detergents CHAPS and deoxycholate lead to alkalinization of the medium whereas lysophosphatidylcholine (LPC), a detergent with structural similarity to PAF, shows no effect.