Angiotensin II-induced contraction of superior mesenteric arteries from streptozotocin-induced diabetic rats

Diabetes is a major risk factor for vascular diseases, and often associated with vascular dysfunction. However, the mechanisms of vascular dysfunction in diabetes are not fully understood. Inactivation of myosin light chain phosphatase thorough myosin phosphatase targeting subunit 1 phosphorylation by Rho kinase is important for angiotensin II (Ang II)-induced contraction. We have previously reported that Rho kinase activation by Src, epidermal growth factor receptor (EGFR), extracellular signal-regulated kinase 1 and 2 (Erk1/2) is involved in protein tyrosine phosphatase inhibitor-induced contraction. We therefore investigated the effects of inhibitors of these factors on Ang II-induced contraction in diabetic rat superior mesenteric arteries.