Effect of previous nutritional status on the formation of cholesterol gallstones in the prairie dog.
In the prairie dog model of cholesterol cholelithiasis, a high incidence of gallstones is achieved by feeding a semipurified lithogenic diet containing 0.4% cholesterol for 2 mo. On occasion, we noted a decrease in the percentage of animals with gallstones from 90-100% to 50-55%. To explain this phenomenon, we studied the effect of dietary history on gallstone formation. After weaning, animals were fed either rodent chow or alfalfa plus corn (mo 0-3) followed by a cross-over experiment at mo 4-6. Gallstone formation then was studied by feeding the lithogenic diet from mo 7 to 8. At sacrifice, the incidences of gallstones, biliary lipids and tissue cholesterol levels were correlated with dietary history. The incidence of gallstones was 100% only in animals fed the alfalfa-corn diet from weaning to 3 mo. In addition, the feeding of the alfalfa-corn diet at mo 4-6 increased gallstone incidence from 65% to 86%. The lithogenic index of all groups was highest when the animals received only alfalfa-corn prior to the lithogenic stimulus. The activity of hepatic HMG-CoA reductase was elevated in animals fed alfalfa-corn from weaning to 8 mo, suggesting that this diet stimulates hepatic cholesterol synthesis, leading to increased biliary cholesterol secretion. It is concluded that previous nutritional conditioning affects the incidence of gallstones. The prairie dog is a useful model of cholesterol cholelithiasis, but the dietary history of the animals plays an important role in lithogenesis.
Cohen
B I
BI
Department of Surgery, Beth Israel Medical Center, New York, NY 10003.
Mosbach
E H
EH
McSherry
C K
CK
D000818:Animals; D001646:Bile / Q000032:analysis; D002769:Cholelithiasis / Q000032:analysis / Q000209:etiology*; D002784:Cholesterol / Q000032:analysis*; D002791:Cholesterol, Dietary / Q000009:adverse effects*; D002849:Chromatography, Gas; D004032:Diet; D008401:Gas Chromatography-Mass Spectrometry; D008055:Lipids / Q000032:analysis; D008297:Male; D008862:Microsomes, Liver / Q000201:enzymology; D012589:Sciuridae / Q000378:metabolism*
D002791:Cholesterol, Dietary; D008055:Lipids; D002784:Cholesterol