Absorption Of Radioactive Iron Research Articles

Effects of the pyrones, maltol and ethyl maltol, on iron absorption from the rat small intestine

The pyrones, 3-hydroxy-2-methyl-4-pyrone (maltol) and 3-hydroxy-2-ethyl-4-pyrone (ethyl maltol) chelate iron with a high affinity and selectivity. The resulting 1:3 (metal-ligand) complexes, being neutral, are able to partition readily across cell membranes and thus may facilitate iron transport across the intestinal wall. Absorption of radioactive iron (59Fe) in the presence of these pyrones was investigated in male rats 1, 2, 4 and 6 h after intraduodenal administration of a 7 micrograms dose and compared with that of 59Fe given as the sulphate, gluconate, fumarate or complexed to EDTA. Total body absorption and distribution were calculated from the 59Fe content of various tissue samples. With all the iron preparations used, blood levels of 59Fe were highest 1 h after injection whilst the 59Fe content at the major site of deposition, i.e. the bone marrow, increased up to 6 h. No 59Fe was found in the urine. Total body absorption of 59Fe was significantly higher from the pyrones than from the other four preparations. Over the dose range 0.7-700 micrograms, the proportion of 59Fe absorbed from both iron maltol and iron sulphate decreased with increasing dose. Enhanced 59Fe uptake from maltol was evident at 0.7-70 micrograms but not at 700 micrograms suggesting that use of these pyrones will not result in iron overload. Absorption of 59Fe given into the stomach was slower in onset but was sustained longer presumably via a steady delivery of iron to the duodenum from the gastric reservoir.(ABSTRACT TRUNCATED AT 250 WORDS)

ABSORPTION OF RADIOACTIVE IRON BY CHILDREN

Absorption of Radioactive Iron by Children Nutrition Reviews, Volume 5, Issue 7, July 1947, Pages 211–213, https://doi.org/10.1111/j.1753-4887.1947.tb04208.x Published: 01 July 1947

Iron absorption in experimental uremia.

Gastrointestinal absorption of radioactive iron (59Fe) was studied in uremic rats. Duodenal gut sac transport of 59Fe in a group of 12 rats with a mean BUN of 98+/-24.4 mg%, was 2.29+/-1.16. This was significantly lower (p less than 0.01) than the amount of 59Fe transported (4.88+/-1.87) across the duodenum of a group of control rats, mean BUN 22.9+/-3.2 mg%. We conclude that there is diminished absorption of iron in uremia.

Patterns of food iron absorption in iron-deficient white and indian subjects and in venesected haemochromatotic patients.

The absorption of radioactive iron from a solution of ferrous ascorbate, and from a standard meal containing intrinsically labelled haemoglobin and wheat, was measured in 12 Indian housewives, 18 white hospital patients and 12 subjects with idiopathic haemochromatosis. Eight of the latter had been fully treated by multiple venesections, so that their serum ferritin concentrations were below 25 mug/1. Since the serum ferritin concentrations of the housewives and the hospital patients were comparable, their body iron stores were considered to be depleted to a similar degree. There were no significant differences between the absorptions of ferrous ascorbate or of the haem iron in the standard meal by each group, but the housewives and the hospital patients absorbed significantly less of the non-haem food iron. The mean non-haem food iron absorptions were 36.4%, 5.8% and 18.9% for the treated haemochromatotic subjects, the Indian housewives and the white hospital patients respectively. The discrepancies between the absorptions of the different forms of food iron were highlighted by calculating the ratios between them. The mean non-haem: haem food iron absorption ratio for the group of treated haemochromatotic subjects was 0.98, and for the Indian housewives only 0.18. The white hospital patients did not form a homogenous population: the ratios of the five males and three of the females were greater than 1.0, whereas those of the remaining 10 females were less than 0.5. The results of this study suggest that mal-absorption of non-haem iron from a meal containing bread, presumably due to a defect at the luminal level, may be an important factor in the pathogenesis of iron deficiency in some subjects. The abnormality appears to be particularly prevalent among Indian women living in Durban.

Physiologische Untersuchungen an der Mutante chloronerva von Lycopersicon esculentum Mill.: III. Über die Komplexbildung des ‚Normalisierungsfaktors‛ mit Eisen und Kupfer )

Absorption of radioactive iron through the upper epidermis of young leaves occurs to the same extent in the mutant and its wild type ‘Bonner Beste’. The absorption is inhibited both by addition of 0.002 % up to 0.01 % of ‘normalizing factor’ and by amounts of Na2 EDTA equivalent to the amount of iron added. Complex formation between iron and the ‘normalizing factor’ has been proved by ORD spectroscopy. It is limited to the trivalent state of iron and prevented by citric acid. Complex formation may be relevant for short-distance iron transport in roots and leaves. A complex is also formed between the ‘normalizing factor’ and copper. Its stability is demonstrated by thin layer chromatography using Kieselgel G and phenol — water 3 : 1 as solvent.

Absorption of Iron from the Small Bowel of Dogs

Summary Absorption of radioactive iron from segments of duodenum and ileum in anesthetized dogs was concurrently measured by three different methods. Agreement among the results of the three methods was close. Iron was given in either ferric or ferrous form in doses of 0.5 to 10 μg. In some instances ascorbic acid (100 mg.) was added to the test solution of iron in Tyrode's solution; the pH of the solution was adjusted to 2 or 7 before placement in the intestinal loops. Most tests lasted 5 hours. A linear relationship was obtained on a log/log scale between the amount of iron absorbed and the amount in the test solution. The relationship was most significant when the test solution was at pH 2 and contained ascorbic acid. The addition of ascorbic acid or acidifying the iron solution to pH 2 caused similar increases in absorption of iron; the effects were additive. When the iron was in a solution at pH 2 with ascorbic acid added, significantly more iron was absorbed from the duodenum per square centimeter of serosa than from the ileum. The rate of absorption of iron was fastest in most cases in the 15-minute period from 15 to 30 minutes after introduction of iron into the lumen of the bowel. This maximal rate did not bear any relation to the total amount of absorption of iron. In most cases absorption did not continue longer than 120 minutes. Three doses of radioactive iron given at 2-hour intervals into the same segment of duodenum resulted in only slight diminution of absorption of iron, showing that the so called mucosal block did not operate at these dose levels. It is suggested that after about 1 hour the iron remaining in the lumen of the bowel had no further influence on absorption of iron; only the iron accumulated in the intestinal wall during the first hour was subsequently absorbed. During the absorptive period, the radioiron left the fluid contents of the intestinal loop more rapidly than it left the intestine. The resulting accumulation in the mucosa was demonstrated autoradiographically.

Absorption of radioactive iron by anaemic infants.

Absorption of radioactive iron by anaemic infants.

Absorption of radioactive iron and its assimilation by erythrocytes in anemia caused by partial denervation of the stomach

Long term experiments were performed on dogs with experimental anemia induced by denervation of the stomach (by Klemensiewicz-Heidenhain partial denervation or by section of the vagus nerves). Investigation was carried out on the absorption of radioactive iron (Fe59Cl3) in the digestive tract and its intake by the erythrocytic hernoglobin.

Absorption of radioactive iron in normal, anemic and hemochromatotic subjects

Absorption of radioactive iron in normal, anemic and hemochromatotic subjects

Hemosiderosis and the parenteral administration of iron.

Editorial1 February 1952HEMOSIDEROSIS AND THE PARENTERAL ADMINISTRATION OF IRONP. W. C.P. W. C.Search for more papers by this authorAuthor, Article, and Disclosure Informationhttps://doi.org/10.7326/0003-4819-36-2-694 SectionsAboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissions ShareFacebookTwitterLinkedInRedditEmail ExcerptThe extensive deposition of hemosiderin granules in the cells of the liver and other organs is known to occur in three clinically distinct pathologic states: In idiopathic hemochromatosis, in severe malnutrition with pellagra as observed in South African negroes, and following repeated transfusions of blood. It now seems certain that this may also be brought about by the excessive or protracted parenteral administration of iron. As commercial preparations of iron are now available which can be administered intravenously in effective doses without causing immediate severe reactions, the possible harmful effect of such pigment promises to become a question of immediate...1 DubachCallenderMoore RSTCV: Studies in iron transportation and metabolism. VI. Absorption of radioactive iron in patients with fever and with anemias of varied etiology, Blood 3: 526-540, 1948. CrossrefMedlineGoogle Scholar2 Granick S: Iron metabolism and hemochromatosis, Bull. New York Acad. Med. 25: 403-428, 1949. MedlineGoogle Scholar3 BrownMoore EBCV: Saccharated iron oxide intravenously in hypochromic anemia, J. A. M. A. 144: 1084-1089, 1950. CrossrefMedlineGoogle Scholar4 Finch CA: Utilization of intravenous radioactive iron, Blood 4: 905-927, 1949. CrossrefMedlineGoogle Scholar5 Nissim JA: Intravenous administration of iron, Lancet 2: 49-51, 1947. Nissim, J. A., and Robson, J. M.: Intravenous treatment of anaemia with an ironsucrose preparation, Lancet 1: 326-327, 1949. CrossrefMedlineGoogle Scholar6 Holly RG: Intravenous iron: Evaluation and use of saccharated iron oxide in iron deficiency states in obstetrics and gynecology, Blood 6: 1159-1172, 1951. CrossrefMedlineGoogle Scholar7 Polson CJ: The failure of prolonged administration of iron to cause haemochromatosis, Brit. J. Exper. Path. 14: 73, 1933. Google Scholar8 Cappell DF: The late results of intravenous injection of colloidal iron, J. Path. and Bact. 33: 175, 1930. CrossrefGoogle Scholar9 Gillman J: A comparison of chemical and histological estimations of the iron and copper content of the livers of Africans in relation to the pathogenesis of cytosiderosis and cirrhosis (haemochromatosis), South African J. M. Sc. 10: 109-136, 1945. Gillman, J., and Gillman, T.: The pathogenesis of cytosiderosis (haemochromatosis) as evidenced in malnourished Africans, Gastroenterology 8: 19-23, 1947. MedlineGoogle Scholar10 SchwartzBlumenthal SOSA: Exogenous hemochromatosis resulting from blood transfusions, Blood 3: 617-640, 1948. CrossrefMedlineGoogle Scholar11 Chesner C: Hemochromatosis. Review of literature and presentation of a case without pigmentation or diabetes, J. Lab. and Clin. Med. 31: 1029-1936, 1946. MedlineGoogle Scholar12 Kark RM: Two cases of aplastic anaemia. One with secondary haemochromatosis following 290 transfusions in nine years, and the other with secondary carcinoma of the stomach, Guy's Hosp. Rep. 87: 343-353, 1937. Google Scholar13 HumphriesSouthworth GHH: Aplastic anemia terminated by removal of a mediastinal tumor, Am. J. M. Sc. 210: 501-510, 1945. CrossrefGoogle Scholar14 DavisArrowsmith WDWR: The effect of repeated bleeding in hemochromatosis, J. Lab. and Clin. Med. 36: 814-815, 1950. (Abstract.) MedlineGoogle Scholar This content is PDF only. To continue reading please click on the PDF icon. Author, Article, and Disclosure InformationAffiliations: PreviousarticleNextarticle Advertisement FiguresReferencesRelatedDetails Metrics Cited byHEMOCHROMATOSIS AND HEART FAILURE: PRESENTATION OF A CASE WITH SURVIVAL AFTER THREE YEARS' TREATMENT BY REPEATED VENESECTION*SAUL J. GROSBERG, M.D.Hemosiderosis and Hemochromatosis: The Question of PathogenesisHAEMOCHROMATOSIS WITH HEART FAILURE COMPLICATING CONGENITAL NON-SPHEROCYTIC HAEMOLYTIC ANAEMIAHemochromatosis and transfusional hemosiderosisHemochromatosis after prolonged oral iron therapy in a patient with chronic hemolytic anemiaCirrhosis of the Liver: Natural History of a Disease 1 February 1952Volume 36, Issue 2_Part_2Page: 694-699KeywordsBlood cellsBlood transfusionCellsEffective doseHemochromatosisLiverMalnutrition Issue Published: 1 February 1952 PDF downloadLoading ...

STUDIES IN IRON TRANSPORTATION AND METABOLISM: VI. Absorption of Radioactive Iron in Patients with Fever and with Anemias of Varied Etiology

Abstract 1. The isotope technic for studying iron absorption has been extended to measure the unabsorbed isotope in feces as well as the amount synthesized into hemoglobin. The recovery of radioiron from feces was shown to be accurate within 10 per cent. 2. There was suggestive evidence to indicate that, with the 1 mg. per kilogram dose employed, normal subjects may sometimes absorb more iron than is converted within a two week period into hemoglobin. 3. Patients with fever, untreated pernicious anemia, and refractory anemia were shown to absorb more iron than they use for hemoglobin. 4. Patients with hemolytic anemia may absorb more iron than can be recovered in the peripheral blood at any one time because isotopic hemoglobin is removed from the circulation at a rapid rate. 5. Except in afebrile patients with hypochromic anemia, acceptance of the per cent of a given dose of radioiron which appears in circulating hemoglobin as a measure of iron absorption must be made with caution. 6. The theory that mucosal cells accept iron for absorption or block its assimilation provides the best known explanation for iron absorption; but patients with adequate iron stores may assimilate considerable quantities of the metal and the block must be regarded as relative.

Lack of Effect of Secondary Liver Extract (No. 55) on Absorption of Radioactive Iron.

SummaryIron tagged with the radioactive isotope Fe59 was fed with and without supplements of liver extract No. 55 to a group of 11 normal adult women. There were no obvious differences in the absorption and utilization of iron when this material was given alone or in conjunction with the “secondary anemia fraction of liver.” In one case of human iron deficiency due to multiple acute and chronic hemorrhage there was also no difference in the absorption of iron as indicated by this method.The “summation response” described by Whipple, Robscheit-Robbins and Walden is apparently not related to the effect of the secondary liver extract on absorption of iron in the gastro-intestinal tract.

The Absorption of Radioactive Iron by Children 7–10 Years of Age: Two Figures

Determinations of iron absorption on 176 school children, aged 7–10 years, have indicated a mean uptake of 7.75 to 17.75% of a test dose of 2–3 mg of ferrous iron. The median intakes were slightly lower. The uptake was found to be correlated with the estimated yearly increases of body iron during growth; it was not correlated in these children with other factors tested for, such as economic status of the group, dietary intake as estimated, the hemoglobin level, or general nutritive state. A new method for the calculation of iron requirements is outlined. It is estimated from these data that the mean daily requirement of absorbable iron is 2.3–3.8 mg for children of this age group. It appears that the mean level of approximately 13 gm of hemoglobin in these children was not limited by iron deficiency.