Isolation and Quantification of Neutral and Acidic Steroids in Feces

Abstract

In the steady state the daily fecal excretion of neutral plus acidic steroids of endogenous origin should approximately equal the daily synthesis of cholesterol in any species in which the intestine is the major route of excretion, as it is in man. This statement is based on our present understanding of a) the conversion of cholesterol to bile acids in the hver and the degradation of neutral and acidic sterols to a multitude of steroidal secondary products within the intestinal lumen (reviewed recently by Danielsson ¹);b) the resistance of the ring structure of cholesterol to degradation within the body or by intestinal microorganisms²; and c) the finding in the present study that the ring structure and side chain of the two primary bile acids (in man) also remain intact during passage through the intestine or circulation within the enterohepatic system.