Abstract
Dipeptidyl peptidase‐4 (DPP‐4) inhibitors which are used to treat hyperglycaemia in type 2 diabetes may exert beneficial cardiovascular effects independently of their glucose lowering action. We hypothesized that linagliptin (LNG) treatment (4 weeks, 2 mg/kg per day orally) would improve relaxation in mesenteric arteries (MA) from STZ‐induced diabetic rats. In MA from diabetic rats there was a significant increase in superoxide levels, assayed by lucigenin chemiluminescence (diabetes, 1448± 108 counts/mg versus normal 644±380 counts/mg, n=7‐9, p<0.01). LNG does not reduce high blood glucose levels in diabetic rats (diabetes, 25±2.2 mM versus diabetes+ LNG, 27±1.7 mM). Acetylcholine (ACh)‐induced relaxation of MA was assessed using wire myography (pEC50=7.26±0.13, n = 8). Diabetes significantly reduced the sensitivity to ACh and treatment with LNG improved endothelial dysfunction (pEC50 …