Cholestyramine [koe-LES-tir-a-meen], colestipol [koe-LES-tih-pole], and colesevelam [koh-le-SEV-e-lam] are anion-exchange resins that bind negatively charged bile acids and bile salts in the small intestine (Figure 23.10). The resin/bile acid complex is excreted in the feces, thus lowering the bile acid concentration. This causes hepatocytes to increase conversion of cholesterol to bile acids, which are essential components of the bile. Consequently, intracellular cholesterol concentrations decrease, which activates an increased hepatic uptake of cholesterol-containing LDL particles, leading to a fall in plasma LDL-C. [Note: This increased uptake is mediated by an up-regulation of cell surface LDL receptors.]