Noradrenaline stimulation of the phosphoinositide system: evidence for a novel hydrophobic inositol-containing compound in resistance arterioles.
1. Five inositol phosphates were extracted from adult rat resistance arterioles and separated by ion-exchange high performance liquid chromatography. 2. By use of this technique, inositol phosphates liberated were identified as inositol 1-phosphate, inositol 1,4-bisphosphate, inositol 1,3,4-trisphosphate, inositol 1,4,5-trisphosphate and inositol 1,3,4,5-tetrakisphosphate. Stimulation of phosphoinositide hydrolysis with noradrenaline produced increases in inositol phosphate production. 3. Three inositol-containing phospholipids extracted from resistance arterioles were measured as their glycerol esters following deacylation, thereby permitting an analysis of both membrane and cytosolic components of the phosphoinositide signalling system. 4. A substantial agonist-sensitive pool of a previously undescribed inositol but not glycerol-containing lipid extract component was also identified in this tissue. 5. These experiments for the first time allow a precise description of phosphoinositide metabolism in resting and agonist-stimulated resistance arterioles and provide data on a novel compound possibly similar to that recently described in other tissues.
Ollerenshaw
J D
JD
Department of Medicine, Leicester Royal Infirmary.
Heagerty
A M
AM
Swales
J D
JD
D000818:Animals; D001158:Arteries / Q000378:metabolism*; D001160:Arterioles / Q000187:drug effects / Q000378:metabolism*; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D005260:Female; D009638:Norepinephrine / Q000494:pharmacology*; D010716:Phosphatidylinositols / Q000032:analysis* / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains
D010716:Phosphatidylinositols; D009638:Norepinephrine