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Aryl hydrocarbon hydroxylase activity was detectable in cultured macrophage monolayers of peripheral blood monocyte origin. Peripheral blood monocytes were isolated from patients with biopsy-confirmed liver disease and healthy volunteers. Macrophage monolayers were prepared and incubated at 37 degrees C. After 24 hr, the aryl hydrocarbon hydroxylase activity and cellular protein concentration were assayed on cell homogenates. The monocyte aryl hydrocarbon hydroxylase activity in cultured macrophages from normal volunteers was 1.23 +/- 0.16 (n = 19). The aryl hydrocarbon hydroxylase activity in macrophage cultures from patients with biopsy-confirmed liver disease was 0.48 +/- 0.05 (n = 20). This represents a significant (61%) decrease in monocyte aryl hydrocarbon hydroxylase compared to controls. The 20 patients have established cirrhosis or early stage liver disease. The established cirrhosis group includes alpha 1-antitrypsin deficiency-associated cirrhosis; primary biliary cirrhosis; alcoholic (Laennec's) cirrhosis; cryptogenic cirrhosis, and hemochromatosis. Early stage liver disease is attributed to methotrexate (Stage III), early stage primary biliary cirrhosis and alpha 1-antitrypsin deficiency. Our results indicate that the depression in monocyte aryl hydrocarbon hydroxylase activity is greater in patients with established cirrhosis than early stage liver disease. Our results further suggest that cultured monocytes from patients with liver disease spontaneously release soluble factors into the culture medium. Incubation of this medium, containing macrophage factors, with isolated hepatocytes significantly depress hepatocyte aryl hydrocarbon hydroxylase activity compared to medium obtained from cultures of monocytes from normal volunteers.(ABSTRACT TRUNCATED AT 250 WORDS)

The effects of treadmill exercise on platelet function, blood coagulability and fibrinolytic activity were evaluated in 20 patients with lone atrial fibrillation (AF) and 15 age-matched normal controls (normals). Multistage treadmill exercise up to 85% of the predicted maximal heart rate was performed, and blood for measurements was obtained pre-exercise, and immediately and 6 min post-exercise. There was an increase in the platelet sensitivity to ADP-aggregation after exercise in both groups. Pre-exercise plasma beta-thromboglobulin (beta-TG) levels were higher in AF than in normals. Beta-TG increased after exercise in both groups (immediate post-exercise; 35.1 ng/ml for normals and 62.8 ng/ml for AF), and the increase was greater in AF than in normals. PT and APTT shortened, and plasma fibrinogen levels increased after exercise in both groups. Pre-exercise levels of plasma ATIII and protein C were lower in AF than in normals. These two proteins increased after exercise in both groups. However, the increase was greater in normals. Plasma alpha 2-PI increased after exercise in both groups; the level was lower in AF than in normals at each exercise stage. In conclusion, enhanced platelet activity, and lower levels of anticoagulant and antifibrinolytic activity were observed in AF not only at rest but also after treadmill exercise. These changes might reflect the hypercoagulable state in patients with AF. It is speculated that the risk of thromboembolic complications may be enhanced with exercise in AF patients.

The effects of induced hyperglycemia on both antithrombin III (ATIII) biologic activity and plasma concentration in normal subjects are reported. A decrease in ATIII activity parallel to hyperglycemia was observed, while ATIII concentration was unchanged. When the glycemia returned to basal values ATIII activity concomitantly showed values in the basal range. Heparin infusion was able to significantly preserve ATIII activity from glycemia-induced alterations. These data demonstrate that hyperglycemia by itself may alter ATIII biologic activity. Moreover, the effect of heparin administration suggests that both glucose and heparin compete in vivo for the same functional site. Our study, showing the possible role of hyperglycemia in altering the biologic function of some proteins, stresses the role of increased blood glucose in the development of some complications in diabetes.