Enhancement of interleukin-1beta-induced iNOS expression in cultured vascular smooth muscle cells of Goto-Kakizaki diabetes rats.
The purpose of this study was to determine whether expression of inducible nitric oxide synthase (iNOS) is altered in vascular smooth muscle cells of type 2 diabetes rats. We used cultured aortic smooth muscle cells (ASMCs) isolated from male Goto-Kakizaki diabetes rats (G-K rats) aged 27-28weeks and age-matched Wistar rats (control rats). iNOS and extracellular signal-regulated kinase (ERK) were evaluated by immunoblot and/or immunochemical analyses, and NO production was evaluated by measuring NO(X) (NO(2) and NO(3)). Expression of iNOS was not detected in ASMCs of either G-K or control rats under a resting condition. Stimulation with interleukin-1beta (IL-1beta) induced iNOS expression, which was much greater in ASMCs from G-K rats than in ASMCs from control rats. When ASMCs were stimulated with IL-1beta, the number of iNOS-immunoreactive ASMCs from G-K rats increased more prominently than did the number of such ASMCs from control rats. IL-1beta-induced NO production was also much greater in ASMCs from G-K rats than in those from control rats. Both IL-1beta-induced iNOS expression and NO production in ASMCs of G-K and control rats were markedly reduced in the presence of an ERK inhibitor, U0126 or PD98059. Both basal and IL-1beta-stimulated levels of ERK activity were significantly higher in ASMCs from G-K rats than in ASMCs from control rats. The results suggest that iNOS induction is enhanced in cultured ASMCs from G-K rats and that this enhancement is associated with increased ERK activity.
Wakabayashi
Ichiro
I
Department of Environmental and Preventive Medicine, Hyogo College of Medicine, Nishinomiya, Hyogo 663-8501, Japan. wakabaya@hyo-med.ac.jp
Nakano
Tomoyuki
T
Takahashi
Yuji
Y
D000818:Animals; D001011:Aorta / Q000473:pathology; D001786:Blood Glucose / Q000378:metabolism; D001835:Body Weight / Q000187:drug effects; D002478:Cells, Cultured; D003920:Diabetes Mellitus / Q000097:blood / Q000235:genetics / Q000378:metabolism* / Q000473:pathology*; D004790:Enzyme Induction / Q000187:drug effects; D048049:Extracellular Signal-Regulated MAP Kinases / Q000378:metabolism; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects*; D053583:Interleukin-1beta / Q000494:pharmacology*; D008297:Male; D009131:Muscle, Smooth, Vascular / Q000378:metabolism* / Q000473:pathology*; D009569:Nitric Oxide / Q000096:biosynthesis; D052247:Nitric Oxide Synthase Type II / Q000096:biosynthesis / Q000378:metabolism*; D051381:Rats
D001786:Blood Glucose; D053583:Interleukin-1beta; D009569:Nitric Oxide; D052247:Nitric Oxide Synthase Type II; D048049:Extracellular Signal-Regulated MAP Kinases