Extracellular Ca2+ influences 1,2-diacylglycerol and inositol monophosphate formation in renal cortical slices stimulated with plasma obtained from uninephrectomized rats.
Formation of 1,2-diacylglycerol (DAG) and inositol phosphates was investigated in renal cortical slices after addition of plasma obtained 30 min after either uninephrectomy or sham operation. Plasma from uninephrectomized rats increased DAG concentration about 100% above control value during 5 min of incubation, but when extracellular Ca2+ had been chelated with 4 mM EGTA, the increase of DAG was only about 50% and the duration of the effect was 2 min only. Furthermore, chelation of extracellular Ca2+ did not affect the formation of InsP3 and InsP2 during 20 min of incubation, while the formation of InsP was significantly reduced. Results indicate that extracellular Ca2+ is needed for sustained increase in DAG concentration and increase in InsP radioactivity, suggesting phosphatidylinositol as their probable source.
Banfić
H
H
Department of Physiology, Faculty of Medicine, University of Zagreb, Yugoslavia.
D000818:Animals; D002118:Calcium / Q000378:metabolism / Q000502:physiology*; D004075:Diglycerides / Q000096:biosynthesis*; D005260:Female; D005989:Glycerides / Q000096:biosynthesis*; D006868:Hydrolysis; D007295:Inositol Phosphates / Q000096:biosynthesis*; D007672:Kidney Cortex / Q000378:metabolism*; D009392:Nephrectomy; D010949:Plasma; D051381:Rats; D011919:Rats, Inbred Strains; D013403:Sugar Phosphates / Q000096:biosynthesis*; D010738:Type C Phospholipases / Q000378:metabolism
C011439:1,2-diacylglycerol; D004075:Diglycerides; D005989:Glycerides; D007295:Inositol Phosphates; D013403:Sugar Phosphates; D010738:Type C Phospholipases; D002118:Calcium