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Query: UMLS:C0038187 (starvation)
 24,951 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The development of siderosis of liver and spleen was investigated in rats subjected alternately to periods of starvation and periods of feeding of diets rich in iron (0.71% or 1.23% Fe) or of control diets, during periods ranging up to 245 days. With 0.71% iron in the diet, cyclic starvation-feeding markedly enhanced the accumulation of iron in rat livers by comparison to feeding ad libitum even though rats fed ad libitum ingested far greater total amounts of iron than cyclically fed rats. With 1.23% iron in the diet, the concentration of iron in livers reached more or less the same plateau in cyclically starved-fed rats and in rats fed ad libitum (betwen 4 and 5 mg Fe/g wet weight); but the mean rate of accumulation of iron in the livers of cyclically starved and fed rats was more than twice that in rats fed ad libitum, whereas mean ingestion of iron per feeding day was only 16% higher in the former group. Surgical removal of the spleen enhanced the accumulation of iron in the liver in cyclically starved-fed rats and in rats fed ad libitum. Histologically, siderosis of the liver was moderate in rats fed the diet with 0.71% iron but was severe in rats fed the diet with 1.23% iron and most severe in those without spleens. Stainable iron was deposited in hepatocytes and in Kupffer cells. None of the rats developed cirrhosis of the liver. The data suggest that in rats a barrier to the absorption of iron from the gut, or to its later utilization, is surmounted if the concentration of iron in the food exceeds a certain limit value, somewhere between 0.71 and 1.23%. With iron in the food below this value, cyclic starvation-feeding markedly potentiates accumulation of iron in the liver in the course of several months, but siderosis is moderate. With iron in the food above the limit value, cyclic starvation-feeding and feeding ad libitum can equally lead to massive siderosis of the liver.
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PMID:Effects of cyclic starvation-feeding and of splenectomy on the development of hemosiderosis in rat livers. 481 98

Iron in the tissues of the digestive tract of the common vampire bat (Desmodus rotundus) has been studied using histochemical, electron microscopic, and autoradiographic methods. This animal is an obligate sanguivore and has a daily intake of dietary iron 800 times that of man. The amount and distribution of tissue iron is not affected by either a single blood meal or starvation but does reflect the degree of siderosis of each animal's liver and spleen. By 7 days after the injection of a trace amount of 55Fe into the peritoneal cavity, labelled siderotic macrophages are present both on the serosa and within the walls of the stomach and intestine. In the lower intestine, such cells can be derived from the germinal centers of Peyer's patches. Siderotic macrophages are often situated in the lamina propria under areas of siderotic epithelium. Label is also present in the apical cytoplasm of mucosal epithelial cells, a region of abundant siderosomes. The ultrastructure of these organelles is extremely variable. Accumulations of membranous whorls and stacks, "stippled bodies," ferritin molecules, and larger "ferruginous" complexes are bounded by one or a number of membranes. Iron is excreted when these epithelial cells are desquamated into the gut lumen. Similar Prussian blue-positive granules are present in the feces. Unlike other glandular cells, the parietal cells of the fundic caecum are siderotic. Their cytoplasm contains abundant siderosomes and ferritin with accumulations of amembranous ferritin bodies in the intracellular canalicular spaces. Prussian blue-positive granules are present in the lumens of fundic glands.
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PMID:Distribution of iron in the gastrointestinal tract of the common vampire bat: evidence for macrophage-linked iron clearance. 721 3