[Pathogenesis of gallbladder cholesterolemia].
Disturbances in cholesterol metabolism may be essential in pathogenesis of gallbladder cholesterosis (GBC). HDL cholesterol in the blood is subnormal. Physicochemical changes in the superficial layer of HDL induce impairment of free cholesterol esterification. Blood lipids and their apoprotein component are important for bile cholesterol level. In gallbladder contractile dysfunction but unaffected absorption there is enhanced passive and active cholesterol transport from the supersaturated bile to the cytoplasm of the epithelial cells from the bladder mucosa. Mechanism of intensive absorption of the lipids by macrophages operates primarily via modification of their apoprotein component. Modification of apoprotein occurs both in blood and gallbladder. Modified apoprotein is recognized by the macrophage and is absorbed by it together with transported lipids. In accumulation of great quantities of lipids in the macrophage it becomes big, slow, stays in the mucous or submucous layer of the wall and finally transforms into the foam cell. Moreover, deterioration of HDL cholesterol acception in GBC leads to slow discharge of cholesterol from the bladder wall.