To Estimate the Amount of Total Cholesterol in Serum
Cholesterol is a solid alcohol found exclusively in animals and contains 27 carbon atoms (C27H46O). It possesses a ring structure called cyclopentanoperhydrophenanthrene. It is a major component of biological membranes and lipoproteins and amphipathic in nature. It is a precursor in many metabolic pathways including synthesis of vitamin D, steroid hormones, and bile acids. About 400–700 mg of cholesterol present in the gut is contributed by biliary secretion and the turnover of mucosal cells. The cholesterol present in the intestine is the unesterified form. This form is solubilized by the formation of mixed micelles that contain the unesterified cholesterol, fatty acids, monoglycerides, phospholipids, and conjugated bile acids. Maximum absorption of cholesterol occurs in small intestine. Total cholesterol contains free cholesterol and esterified cholesterol in the ratio 1:3.