title: Angiotensin II increases glucose uptake and glucose transporter-1 mRNA levels in astroglia.
abstract: In this study, we have investigated the effects of angiotensin II (ANG II) on glucose uptake into astroglia cultured from adult rat hypothalamus and brain stem. ANG II (30 min to 4 h; 10(-9) to 10(-6) M) stimulated time- and concentration-dependent increases in the uptake of 2-deoxy-D-[3H]glucose into cultured astroglia. This effect of ANG II (10(-7) M) is via AT1 receptors and protein kinase C (PKC), since it was inhibited by losartan (10(-6) M) and staurosporine (10(-6) M), respectively. Furthermore, this ANG II action was inhibited by both cycloheximide (1 microgram/ml) and actinomycin D (10(-6) M), indicating that synthesis of new glucose transporters is involved. This was confirmed by the finding that ANG II (30 min to 4 h; 10(-9) to 10(-5) M) stimulated time- and concentration-dependent increases in the steady-state levels of glucose transporter-1 (GLUT-1) mRNA in these cultures. In addition, the increase in steady-state levels of GLUT-1 mRNA elicited by ANG II was mediated by AT1 receptors and PKC. These data suggest that ANG II stimulates glucose uptake into cultured astroglia via a pathway that involves AT1 receptors, PKC, and increased steady-state levels of GLUT-1 mRNA.
authors.affiliation: Department of Physiology, College of Medicine, University of Florida, Gainesville 32610.
authors.forename: W
authors.initials: W
authors.lastname: Tang
authors.forename: E M
authors.initials: EM
authors.lastname: Richards
authors.forename: M K
authors.initials: MK
authors.lastname: Raizada
authors.forename: C
authors.initials: C
authors.lastname: Sumners
mesh_terms: D000804:Angiotensin II / Q000494:pharmacology*; D000818:Animals; D001253:Astrocytes / Q000187:drug effects / Q000378:metabolism*; D001692:Biological Transport / Q000187:drug effects; D002478:Cells, Cultured; D003513:Cycloheximide / Q000494:pharmacology; D003847:Deoxyglucose / Q000378:metabolism; D005947:Glucose / Q000378:metabolism*; D051272:Glucose Transporter Type 1; D007700:Kinetics; D009004:Monosaccharide Transport Proteins / Q000235:genetics*; D011493:Protein Kinase C / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D014316:Tritium
chemical_list: D051272:Glucose Transporter Type 1; D009004:Monosaccharide Transport Proteins; D012333:RNA, Messenger; C495679:Slc2a1 protein, rat; D014316:Tritium; D000804:Angiotensin II; D003513:Cycloheximide; D003847:Deoxyglucose; D011493:Protein Kinase C; D005947:Glucose