Abstract After development of an experimentally induced renal hypertension in rats, elevated concentrations of cholesterol and phospholipids in serum were observed. The additional ligature of the thoracic duct in normotensive and hypertensive animals further increased the lipid content of serum in hypertensive rats and promoted an even more severe hyperlipaemia in normotensive animals. In both experimental groups the hyperlipaemia took a biphasic course. The lipids measured approached their intitial values on the 15th day following the ligature of the ductus thoracicus. Moreover the ligature of the thoracic duct modified the total lipid content of the liver and induced pronounced morphological alterations of liver tissue.