[Local changes in prostanoids in arteriosclerosis obliterans]

In order to identify local changes in prostanoids in arteriosclerosis obliterans (ASO), plasma levels of thromboxane B2 (TXB2) and 6-keto-prostaglandin F1 alpha(6-Keto-PGF1 alpha) in cubital venous blood (CV blood), in femoral arterial blood (FA blood) and in femoral venous blood (FV blood) of 27 patients with ASO of lower limbs and of 10 healthy controls were measured by RIA technique. The following results were obtained. 1) In the ASO patients, levels of TXB2 and the ratio between TXB2 and 6-Keto-PGF1 alpha (TXB2/6-Keto-PGF1 alpha) in FV blood of ischemic legs were elevated in comparison to those in CV blood or FA blood of the same group or those in FV blood of the controls. 2) This change was more clearly observed in the femoro-popliteal group, but in the aorto-iliac+ combined group, they were elevated not only in FV blood but also in FA blood. 3) No significant difference was observed between the Fontaine I + II group and the Fontaine III + IV group in these local changes in prostanoids. 4) The severer the angiographic manifestation between the abdominal aorta and the common femoral artery, the higher the plasma TXB2 levels in FA blood. Also, the poorer the peripheral run-off, the higher the plasma TXB2 production in the legs. These results suggest that the imbalance between TXA2 and PGI2 is obvious in ischemic legs of ASO patients, TXA2 is elevated downstream from damaged vessels, and the local plasma TXB2 levels reflect the severity of the vascular damage in ASO patients.