Hypofibrinolysis caused by increased PAI-1 levels in patients with insulin resistance (IR) is one of the most common aquired prothrombotic states with higher risk of arterial thrombosis associated with atherosclerosis. Increased PAI-1 levels are caused by PAI-1 hyperproduction in various compartments owing to various factors (multicompartmental and multifactorial model). Metabo- lic compartment, including visceral adipocytes and hepatocytes, is sensitive on stimulative action of insulin, proinsulin and some cytokines. This pool is responsible for elevated PAI-1 levels in obesity. Vascular compartment, including mainly endothelium, is sensitive on thrombin, angio- tensin IV, cytokines, biological active lipids and oxidative stress effect, while insulin inhibites cytokine induced PAI-1 production on contrary. This compartment is responsible for elevated PAI-1 levels in patients with type 2 diabetes mellitus and hypertension with endothelial dysfunci- ton. PAI-1 levels in patients with IR represent cumulative production in described compartments.

        Key words: PAI-1 - Insulin resistance.