A moderate fish intake increases plasminogen activator inhibitor type-1 in human volunteers.

For a period of 6 weeks, 76 healthy male volunteers consumed during their daily main meal the contents of one tin (approximately 135 g) of either fish (mackerel) paste or meat paste. Fibrinolytic parameters were determined in plasma samples obtained at the beginning and at the end of the experimental period. No changes were found in plasminogen, alpha 2-antiplasmin, tissue-type plasminogen activator (t-PA) antigen, and euglobulin t-PA activity. In the control group (n = 39), plasminogen activator inhibitor activity did not change. In the fish group (n = 37), however, total plasma PA inhibitor (PAI) activity increased by 45%, due to a 71% increase in PA inhibitor type-1. This increase could not be ascribed to a diet-induced acute phase-type reaction and could not be explained by changes in serum triglycerides or insulin.