[Stimulation by vasopressin of hydrolysis of phosphatidylinositol- 4,5-diphosphate and its relation to prostaglandin biosynthesis in the bladder epithelium of frogs].
In experiments carried out on the frog urinary bladder, it was found that 20 sec after vasopressin was added, the content of 1,2-di-acylglycerol, labelled with [3H]-arachidonic acid, increased by 44% and the content of [3H]-phosphatidylinositol-4,5-diphosphate (PIP2) decreased by 22%. Five minutes after hormone addition the amount of prostaglandin E (PGE) released into the serosal solution was increased three-fold. Preincubation of bladders in 10(-4) M neomycin led to a 26% increase in vasopressin-stimulated water flow, a block of PIP2 breakdown, and a reduction in PGE synthesis of 62%. A significant decrease in content of lipids labelled with [3H]-arachidonic acid was found in 1,2-diacylglycerol and phosphatidylethanolamine (diacyl form). The data obtained suggest that the role of PIP2 breakdown products in negative feed-back regulation of the hydroosmotic action of vasopressin at least in part includes their connection with PGE biosynthesis activation.
Parnova
R G
RG
Firsov
D L
DL
D000818:Animals; D004848:Epithelium / Q000378:metabolism; D006868:Hydrolysis / Q000187:drug effects; D066298:In Vitro Techniques; D010716:Phosphatidylinositols / Q000378:metabolism*; D011458:Prostaglandins E / Q000096:biosynthesis*; D011896:Rana temporaria; D013268:Stimulation, Chemical; D001743:Urinary Bladder / Q000187:drug effects / Q000378:metabolism*; D014667:Vasopressins / Q000494:pharmacology*
D010716:Phosphatidylinositols; D011458:Prostaglandins E; D014667:Vasopressins
Stimuliatsiia vazopressinom gidroliza fasfatidilinozit-4,5-difosfata i ego sviaz' s biosintezom prostaglandinov v épitelii mochevogo puzyria liagushki.