VASODILATORY EFFECTS OF PROPYLTHIOURACIL IN PATIENTS WITH ALCOHOLIC CIRRHOSIS

Background/Aims: An experimental study has shown that propylthiouracil increases portal blood flow in normal rats, Whether propylthiouracil has a similar effect in patients with alcoholic cirrhosis remains to b e demonstrated, The aim of this study was to evaluate the effects of o ral propylthiouracil (300 mg) on systemic and portal hemodynamics in p atients with alcoholic cirrhosis. Methods: Plasma propylthiouracil lev els were also measured by high performance liquid chromatography in fi ve patients with alcoholic cirrhosis. In eight patients with cirrhosis , mean arterial pressure, cardiac output and portal blood flow were ev aluated before and after placebo and propylthiouracil administration. Hemodynamic measurements were performed by the Doppler technique. The plasma peak level of propylthiouracil was achieved at 1.4 +/- 0.1 h in patients with, alcoholic cirrhosis, This time was chosen to express h emodynamic changes. Results: Propylthiouracil administration caused a significant increase in portal blood flow (+16.5%, p < 0.05) in patien ts with alcoholic cirrhosis. This effect was associated with a mild an d significant rise in cardiac output (from 5.8 +/- 0.2 to 6.1 +/- 0.3 1/min, p < 0.05) and a decrease in-pripheral vascular resistance (from 1171 +/- 69 to 1070 +/- 67 dyn . s(-1). cm(-5), p < 0.01), A signific ant correlation was observed between changes in portal blood bow and p eripheral vascular resistance (r = 0.79, p < 0.05). No significant cha nges were observed after placebo. Conclusions: Our findings show that propylthiouracil has a vasodilatory effect in patients with alcoholic cirrhosis. We postulate that this effect could be the mechanism by whi ch propylthiouracil decreases hypermetabolic state, and increases oxyg en delivery to the liver, in patients with alcoholic liver diseases.