The Inositide and Arachidonic Acid Signal System
The concept that inositol phospholipid hydrolysis is a very early event and is responsible for transducing the effect of hormone-receptor stimulation to the cell interior is now widely accepted. The activation of these specific receptors stimulates phospholipase C which degrades membrane-bound phosphatidylinositol 4,5-bisphosphate to produce two second messengers: inositol 1,4,5-trisphosphate, which can liberate Ca2+ from intracellular stores, and 1,2-diacylglycerol, which activates protein kinase C. The membrane-bound transducer that relates the message from the receptor to the phospholipase C seems to be a specific GTP-binding protein, that is referred to as Gp, where p stands for phosphoinositide.
KeywordsArachidonic Acid Human Platelet Pertussis Toxin Inositol Phosphate Hydroxy Acid
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