[The role and mechanism of fatty acids in gallstones].

18 Chinese cases and 37 Japanese cases of gallstones were analyzed according to the procedure of extracting fatty acids in the gallstone. High perforamance liquid chromatography (HPLC), showed that the contents of total fatty acid and free fatty acid in pigment stones were obviously higher than those in black stone or cholesterol stone. The ratio free saturated to total saturated fatty acid is the highest in intrahepatic pigment stone and less in extrahepatic pigment stone, which significantly differs from the latter two kinds of stones. This may indicate that phospholipid in the bile catablizes into free fatty acids involved in the formation of stone under the action of phospholipase in the course of pigment stone formation. The action of phosphoipase A1 is more important than phospholipase A2.