The reserve of tissue plasminogen activator and nitric oxide in endothelium and its relation to vasodilation in diabetic patients / 中华内分泌代谢杂志

ABSTRACT

Objective To study the changes in the endothelial reserve capacity to release tissue plasminogen activator (tPA) and nitric oxide (NO) and its relation to vasodilation and to diabetic angiopathy. Methods The capacity of vascular endothelium to release tPA and NO was examined by venous occlusion of the upper arm. Brachial artery diameter was measured at baseline, during postocclusion reactive hyperemia (flow-mediated endothelium-dependent), and after sublingual nitroglycerol administration (endothelium-independent), using a high resolution ultrasound technique in 15 control subjects and 23 patients with type 2 diabetes mellitus. Vasodilation was expressed as the percentage change relative to the baseline diameter, while endothelial tPA and NO release was expressed as the percentage change relative to the baseline tPA and NO levels. Thickness of the intima of carotid artery was measured using ultrasound imaging. Results There was no significant difference in endothelium-independent vasodilation between control subjects and diabetics. However, significant reductions in endothelium-dependent vasodilation (P