1,2-Diacylglycerols mimic phorbol 12-myristate 13-acetate activation of the sea urchin egg.
Phorbol diesters have been reported to stimulate the Na+/H+ antiport of a variety of cells including sea urchin eggs. Since stimulation of the Na+/H+ antiport is necessary for metabolic derepression during fertilization and protein kinase C is a target of phorbol diesters, enhanced Na+/H+ exchange during fertilization may be a result of protein kinase C activity. Protein kinase C is probably physiologically activated by diacylglycerols, which are derived from hydrolysis of phosphatidylinositol. Treatment of sea urchin eggs with 1,2-diacylglycerols was found to stimulate the Na+/H+ antiport. The 1,3-isomers were without effect. Further, the effects of 1,2-diacylglycerol and phorbol diester are not additive with respect to Na+/H+ exchange. While a direct participation of protein kinase C activity during fertilization remains to be demonstrated, these data support the hypothesis that protein kinase C activity plays a role in fertilization. However, the cytotoxic effect of protein kinase C activators suggests effects associated with their pleiotropic nature.
D000818:Animals; D002352:Carrier Proteins / Q000502:physiology; D003593:Cytoplasm / Q000378:metabolism; D004075:Diglycerides / Q000494:pharmacology*; D005306:Fertilization; D005989:Glycerides / Q000494:pharmacology*; D006863:Hydrogen-Ion Concentration; D009994:Osmolar Concentration; D010063:Ovum / Q000187:drug effects*; D010704:Phorbols / Q000494:pharmacology*; D012617:Sea Urchins / Q000502:physiology*; D017923:Sodium-Hydrogen Exchangers; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology*
C011439:1,2-diacylglycerol; D002352:Carrier Proteins; D004075:Diglycerides; D005989:Glycerides; D010704:Phorbols; D017923:Sodium-Hydrogen Exchangers; D013755:Tetradecanoylphorbol Acetate