EFFECTS OF CYSTINE NIACIN AND TAURINE ON CHOLESTEROL AND BILE ACID METABOLISM IN RABBITS

Male hypercholesteremic albino rabbits were used to test the effects of cystine, niacin and taurine on the plasma and liver cholesterol concentrations and to correlate the results with the concentration of taurine conjugates in the bile of these animals. Niacin at a 0.6 per cent and 1.2 per cent concentration and taurine at a 1.2 per cent concentration in the diet caused a significant reduction in plasma and liver cholesterol. Niacin (1.2 per cent) caused a greater increase in taurine conjugation than 1.2 per cent taurine. Cystine at the 0.3 per cent dietary level caused a significant increase in both plasma and liver cholesterol concentrations. When its concentration in the diet was increased to 2.4 per cent it caused a significant decrease in liver cholesterol and a significant increase in the concentration of taurine conjugates of the bile. The mechanisms of the action of these compounds are discussed. © 1969.