Elevated levels of insulin have been reported to induce both an arterial vasodilation mediated by nitric oxide (NO), and vasoconstriction mediated by endothelin and reactive oxygen radicals. Metformin, used to control blood glucose levels in type 2 diabetes, has also been shown to cause NO-mediated dilation of conduit arteries. It is possible that these contradictory vascular effects are due to a non-direct action on arteries. Therefore, the direct effect of high levels of insulin and metformin infusion on resistance artery diameter was evaluated. Experiments were carried out on the anesthetized pig; blood flow and pressure were measured in the iliac artery. An adjustable snare was applied to the iliac above the pressure and flow measurement site to induce step decreases (3-4 occlusions at 5 min intervals were performed for each infusion) in blood flow, and hence iliac pressure, and the conductance (deltaflow / deltapressure) calculated. Saline, insulin (20 and 40 mUSP/l/min), and metformin (1 microg/ml/min) were infused separately downstream of the adjustable snare and their effect on arterial conductance assessed. Insulin at both infusion rates and metformin caused a significant reduction in peripheral vascular conductance. In conclusion, hyperinsulinemia and metformin infusion constrict resistance arterial vessels in vivo.

• MeSH
• arteria iliaca účinky léků   patofyziologie   MeSH
• celková anestezie * MeSH
• hyperinzulinismus chemicky indukované   patofyziologie   MeSH
• hypoglykemika aplikace a dávkování   farmakologie   MeSH
• intravenózní infuze MeSH
• inzulin MeSH
• krevní tlak MeSH
• metformin aplikace a dávkování   farmakologie   MeSH
• modely nemocí na zvířatech MeSH
• prasata MeSH
• regionální krevní průtok MeSH
• rychlost toku krve MeSH
• vazokonstrikce účinky léků   MeSH
• zvířata MeSH
• Check Tag
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH