Abstract
Increased arterial myogenic tone in an in vitro model of vascular insulin resistance
Microcirculation, p.96
World Congress for Microcirculation, 10th (Kyoto, Japan, 25-Sep-2015–27-Sep-2015)
2015
Abstract
Vascular insulin resistance is characterized by a decrease in endothelial nitric oxide synthase (eNOS) activity and comparatively increased (unbalanced) endothelin activity.Endothelium-dependent vasodilation is impaired but little is known regarding other vascular responses. Using an in vitro model of vascular insulin resistance, this study examined pressure-induced myogenic tone in the rat cremaster muscle artery. Male Sprague Dawley rats (approx. 200 g) were anesthetized (sodium thiopentone, 100 mg/kg i.p.) and the cremaster muscles removed. Pressure-diameter curves over the range 30-120 mmHg were obtained in isolated, cannulated arteries, in both Ca2+-free and normal [Ca2+] solutions. The vessels were then incubated with vehicle solution or insulin (60 lg/mL; intra-lumenal exposure only) for 2 h and the pressure-diameter relationships established again. In arteries incubated with insulin, active myogenic tone was increased at 50, 70, 100 and 120 mmHg, by 20.2 4.8, 12.1 4.8, 13.7 2.4 and 11.6 4.6% respectively (p < 0.05, two-way ANOVA, n = 4 for all). Insulin also decreased passive (maximum) diameter at 50 and 70 mmHg, by 7.3 1.8 and 4.9 1.4% respectively. There was no significant change in myogenic tone or passive diameter in vehicle-incubated arteries, at any pressure. These observations suggest exposure to high concentrations of insulin increases pressure-induced myogenic tone in isolated arteries and decreases artery distensibility. Such effects may play a role in decreased vascularity and tissue blood flow observed in hyperinsulinemia and insulin resistance. P134
Details
- Title
- Increased arterial myogenic tone in an in vitro model of vascular insulin resistance
- Authors
- T V Murphy (Author) - University of New South WalesShaun L Sandow (Author) - University of the Sunshine Coast - Faculty of Science, Health, Education and EngineeringG Ivanov (Author) - University of New South Wales
- Publication details
- Microcirculation, p.96
- Conference details
- World Congress for Microcirculation, 10th (Kyoto, Japan, 25-Sep-2015–27-Sep-2015)
- Publisher
- John Wiley & Sons Ltd.
- Date published
- 2015
- DOI
- 10.1111/micc.12246
- ISSN
- 1073-9688
- Organisation Unit
- School of Health - Biomedicine; University of the Sunshine Coast, Queensland; School of Health and Sport Sciences - Legacy; School of Health and Behavioural Sciences - Legacy
- Language
- English
- Record Identifier
- 99449573402621
- Output Type
- Abstract
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