Involvement of decreased myo-inositol transport in lipopolysaccharide-induced depression of phosphoinositide hydrolysis in vascular smooth muscle.
The mechanism underlying lipopolysaccharide (LPS)-induced depression of phosphoinositide (PI) hydrolysis was investigated using rat aortas. In LPS-pretreated aortas, the 5-hydroxytryptamine-stimulated accumulation of inositol monophosphate and incorporation of exogenous myo-inositol into PIs were significantly less than those in control aortas. Both sodium-myo-inositol cotransporter (SMIT) and phosphatidylinositol transfer protein (PITP) genes were constituently expressed in rat aortas. The mRNA level of SMIT was remarkably lower in LPS-pretreated aortas, while that of PITP mRNA was not affected by LPS. These results suggest that LPS-induced depression of SMIT expression is involved in inhibition of agonist-stimulated PI hydrolysis by LPS.
Sotoda
Yoko
Y
Department of Hygiene and Preventive Medicine, School of Medicine, Yamagata University, Iida-Nishi 2-2-2, Yamagata, Japan.
Negoro
Munetaka
M
Wakabayashi
Ichiro
I
D000818:Animals; D001013:Aorta, Thoracic / Q000187:drug effects / Q000378:metabolism; D001692:Biological Transport / Q000187:drug effects / Q000502:physiology; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism; D019446:Endotoxemia / Q000139:chemically induced / Q000378:metabolism; D006360:Heat-Shock Proteins / Q000235:genetics / Q000378:metabolism; D006868:Hydrolysis / Q000187:drug effects; D066298:In Vitro Techniques; D007294:Inositol / Q000378:metabolism*; D007295:Inositol Phosphates / Q000378:metabolism; D008070:Lipopolysaccharides; D008297:Male; D008565:Membrane Proteins; D009131:Muscle, Smooth, Vascular / Q000187:drug effects* / Q000378:metabolism*; D010716:Phosphatidylinositols / Q000378:metabolism*; D049294:Phospholipid Transfer Proteins; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D012701:Serotonin / Q000494:pharmacology; D027981:Symporters / Q000235:genetics / Q000378:metabolism
D002352:Carrier Proteins; D006360:Heat-Shock Proteins; D007295:Inositol Phosphates; D008070:Lipopolysaccharides; D008565:Membrane Proteins; D010716:Phosphatidylinositols; D049294:Phospholipid Transfer Proteins; D012333:RNA, Messenger; D027981:Symporters; C073884:SLC5A3 protein, human; D012701:Serotonin; D007294:Inositol