The effect of diuretic drugs on lymph flow in experimental ascites

The effect of several diuretic agents on thoracic duct and right lymph trunk lymph flow, and on some other parameters was examined in normal dogs and dogs with ascites produced by the constriction of inferior cava vein. In normal animals furosemide and etacrynic acid in diuretic doses did not influence thoracic duct lymph flow and reduced slightly arterial pressure and GFR (creatinine clearance). Hydrochlorothiazide increased slightly thoracic duct flow. Neither of the drugs had any significant influence on right trunk lymph flow. In dogs with ascites all drugs tested (furosemide, etacrynic acid and mercurophylline) reduced lymph flow in the thoracic duct but had no effect on the flow in the right trunk. The drugs reduced markedly arterial and inferior cava venous pressure. It is concluded that their effect on ascites is not based on enhanced lymphatic absorption and transport but mainly on the reduction of fluid and protein leakage from the liver sinusoids.