EFFECTS OF PROSTAGLANDIN E-1 INFUSION ON LIMB HEMODYNAMICS AND VASODILATORY RESPONSE IN PATIENTS WITH ARTERIOSCLEROSIS OBLITERANS

It is well known that prostaglandin E-1 (PGE(1)) increases peripheral blood now. The aim of this study was to investigate the effects of PGE (1) infusion on the hemodynamics and vasodilatory response of the leg affected by intermittent claudication in patients with arteriosclerosi s obliterans (ASO). Fourteen legs of 8 male patients with ASO were inf used intravenously with PGE(1) (120 mu g/day) for 7 consecutive days. Before the infusion and 5 days after cessation of the infusion, restin g skin and skeletal muscle blood now in the calf and occlusion-induced reactive hyperemic now were measured using plethysmography and a lase r Doppler flowmeter. Clinical symptoms in the legs were assessed by tr eadmill exercise testing. Resting calf blood now was found to have inc reased significantly (skin, from 2.6 +/- 0.1 ml/min/100 g tissue to 2. 9 +/-: 0.1 ml/min/100 g tissue, p < 0.02; skeletal muscle, from 3.1 +/ - 0.2 ml/min/dl tissue to 4.0 +/- 0.5 ml/min/dl tissue, p < 0.02). The re was also a significant reduction in the peripheral vascular resista nce (-17.8 +/- 7.2%, p < 0.05)5 days after the cessation of infusion. The time to the half-maximum post peak of hyperemia was significantly elongated (from 34.6 +/- 5.7 sec to 58.6 +/- 9.2 sec, p < 0.01). Borg' s score of the legs on exercise testing was markedly reduced, and symp tom-free walking distance was increased by an average of 70.9 +/- 15.6 %. In conclusion, PGE(1) infusion has vascular effects on not only res ting calf blood now but also hyperemic now responses. These retentive effects may be due to alteration in vascular functions and/or rheologi cal state as at result of PGE(1)-induced regular enhancement of blood now, rather than the direct vasodilatory effect of the agent.