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K R Osterloh

Publications and source records attributed to K R Osterloh.

4 recordsLinked to original sources
PubMed1987

Intestinal iron absorption and mucosal transferrin in rats subjected to hypoxia.

Three days hypoxia (0.5 atm) increased the haemoglobin and haematocrit values in rats paralleled by enhanced intestinal iron absorption. The destination of recently-absorbed iron was primarily the erythropoietic system, viz. bone marrow, spleen and red cells. Total plasma transferrin, was increased by 30%, but no significant changes in mucosal transferrin were found. No increase in labelling of mucosal transferrin by absorbed iron was observed. These results suggest that mucosal transferrin does not play a major role in the regulation of intestinal iron absorption in hypoxia.

Animals↗
PubMed1987

Computational analysis of density gradient distribution profiles.

A method is presented for the construction of distribution profiles following subcellular fractionation by density gradient centrifugation. The method allows reconstruction of the frequency-density distributions over user-defined density limits, enabling averaging of results from multiple experiments. An alternative format for data presentation, that of relative concentration versus density, is also introduced. This overcomes some practical problems associated with frequency-density distribution profiles. The technique utilizes a direct noniterative approach to curve fitting and can easily be implemented on microcomputers.

Cell Fractionation↗
PubMed1986

Studies on the role of transferrin and endocytosis in the uptake of Fe3+ from Fe-nitrilotriacetate by mouse duodenum.

Addition of iron-binding proteins (human serum transferrin, mouse serum transferrin, human lactoferrin) to the luminal fluid in tied-off segments of mouse intestine in vivo led to reduced 59Fe3+ absorption from 59Fe3+-nitrilotriacetate when compared to 59Fe3+-nitrilotriacetate alone. Assay of transferrin in luminal fluid from tied segments revealed only trace amounts of immunoreactivity. The levels of luminal transferrin are unaltered in chronic hypoxia where iron absorption is significantly enhanced. Studies in vitro revealed that NH4Cl, dansylcadavarine, para-chloromercuribenzoate and trinitrobenzenesulphonate have no effect on initial 59Fe3+ uptake rates from 59Fe3+-nitrilotriacetate, while N-ethylmaleimide (1 mM) caused a 40% inhibition. In vivo 59Fe3+ uptake was unaffected by preincubation of tied-off segments with colchicine (5 mM) for up to 2 h. These results suggest that receptor-mediated endocytosis of transferrin is not a significant mechanism in the uptake of luminal Fe3+ by mouse duodenum.

Animals↗