Cholesterol absorption and turnover in hypercholesterolemic dogs.
Cholesterol absorption was measured in chronically hypercholesterolemic dogs by four methods: the fecal recovery method of Borgström (1969, J. Lipid Res. 10: 331-337), the dual isotope method of Zilversmit and Hughes (1974, J. Lipid Res. 15: 465-473), the recovery of cholesterol in thoracic duct lymph collected continuously for 16 hr after a meal, and the recovery of isotopic cholesterol from the liver and plasma 24 hr after the animals consumed an isotope-containing meal. The four methods showed excellent agreement and indicated that dogs fed a cholesterol-rich synthetic diet absorb 5.2 +/- 0.5 g (mean +/- SD) of cholesterol per day and that cholesterol absorption is reasonably constant from week to week in these animals. Separate estimates of cholesterol excretion indicated that these dogs excreted 4.7 +/- 0.5 g of cholesterol per day, and thus were at or near the steady-state with regard to cholesterol input-output. These data, taken together with a previous report (1981, J. Lipid Res. 22: 598-609), indicate that the canine liver can clear up to 300 mg of chylomicron cholesterol/hr, and support the concept that chylomicron remnants do not contribute significantly to the hypercholesterolemia in these animals.
D000818:Animals; D001646:Bile / Q000378:metabolism; D002784:Cholesterol / Q000097:blood / Q000378:metabolism*; D002791:Cholesterol, Dietary / Q000378:metabolism*; D002914:Chylomicrons; D004285:Dogs; D005243:Feces / Q000032:analysis; D005260:Female; D006937:Hypercholesterolemia / Q000378:metabolism*; D007408:Intestinal Absorption; D008099:Liver / Q000378:metabolism; D008196:Lymph / Q000032:analysis; D008297:Male; D008823:Micelles; D012855:Sitosterols / Q000032:analysis; D012995:Solubility
D002791:Cholesterol, Dietary; D002914:Chylomicrons; D008823:Micelles; D012855:Sitosterols; C025473:gamma-sitosterol; D002784:Cholesterol