GALLSTONES are to a large extent composed of cholesterol. The reason for the precipitation of cholesterol from solution in the bile is unknown but may be assumed to be caused by either changes in the concentration of that substance in bile, or changes in the elements that keep cholesterol in solution. Amongst the latter are the phospholipids.
The main phospholipid in bile is lecithin. Johnson and Nakayama1 found that increase of lecithin in bile could be readily accomplished by oral feeding but the benefits of that increase in lecithin concentration were nullified by a concomitant increase in the cholesterol content of bile.
The experiment reported here was planned to evaluate the effect of changes in thyroid function upon cholesterol and phospholipids in the blood and bile. The experiment was further designed to evaluate these changes in the intact animal and over a long period of time.
Procedure and Method
Thorbjarnarson B, Pitman J. Serum and Bile Lipids in Altered Thyroid Function. Arch Surg. 1967;94(2):231–234. doi:10.1001/archsurg.1967.01330080069018