Cholesterol turnover and tissue distribution in the guinea pig in response to dietary cholesterol
Green, M.H.; Traber, M.; Ostwald, R.
Journal of Nutrition 106(4): 515-528
1976
ISSN/ISBN: 0022-3166 PMID: 1255270 Document Number: 105283
Male Hartley guineapigs, bodyweight 400-500 g, in 2 groups of 15, received freely for 15-17 weeks a stock diet and 5% cottonseed oil without or with cholesterol representing 0.1% of the total diet. The guineapigs were given 94.5 mu Ci [7 alpha -3H]cholesterol by mouth and were killed 0.5-29 days later. Dietary cholesterol caused a significant increase in cholesterol concentration in liver, red blood cells and small intestine, but not in plasma. Most of the increase in total body cholesterol could be accounted for as increase in liver esterified cholesterol. The 0.1% cholesterol diet did not change either the absorption of the tracer cholesterol or the endogenous cholesterol synthesis rate. Steady state cholesterol input-output rate and total traced mass of cholesterol were greater, and mean transit time was longer in the animals on the cholesterol-containing diet. The data suggest that the maintenance of cholesterol homeostasis in the cholesterol-fed guineapig depends on liver accumulation of esterified cholesterol as well as on increased output of cholesterol.