Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.1.3.5 (5'-nucleotidase)
 3,167 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Macrophages (m phi s), important cells in host resistance, undergo a series of biochemical changes during their progression from the resident to the fully activated stage. Both resident and inflammatory m phi s are characterized by some unique properties. In the present study, female BALB/c mice were prenatally treated with 8 mg/kg body weight of chlordane, a cyclodiene poly-chlorinated hydrocarbon that appears to reduce immunocompetence by selectively impairing m phi function. Therefore, we examined functions in m phi s from chlordane-treated mice that had been stimulated with thioglycollate. The 5'-nucleotidase activity, present in high levels in resident m phi s but low levels in inflammatory m phi s was elevated in resident m phi s from vehicle-exposed animals. Conversely, inflammatory m phi s from these animals showed significantly diminished levels of this function. Moreover, chlordane-exposed m phi s, regardless of whether they were resident or inflammatory, exhibited decreased 5'-nucleotidase responses. When a second function, transferrin receptor binding, was analyzed, vehicle-treated inflammatory m phi s displayed high levels of activity whereas the resident m phi s showed very little transferrin binding. However, both resident and inflammatory m phi s from the chlordane-exposed group demonstrated transferrin binding activity similar in magnitude to that of the vehicle-treated inflammatory m phi s. Finally, two-dimensional polyacrylamide gel electrophoresis analysis of m phi s from chlordane-exposed mice have characteristics of normal m phi s that have advanced to the inflammatory stage.
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PMID:In vivo prenatal chlordane exposure induces development of endogenous inflammatory macrophages. 156

Intracellular movement of cell surface 5'-nucleotidase was studied in H4S cells, a rat hepatoma cell line. Surface labelled cells were incubated for various periods at 37 degrees C and treated with neuraminidase at 0 degrees C. Removal of sialic acid residues from glycoproteins results in a change of their isoelectric points. Analysis with isoelectric focusing was then used to distinguish between cell surface and intracellular 5'-nucleotidase. Incubation of 125I-surface-labelled cells at 37 degrees C resulted in a gradual decrease of labelled 5'-nucleotidase at the plasma membrane until, at 60 to 90 min, a steady state was reached with 52% of the label on the cell surface and 48% intracellular. Pretreatment of the cells with the weak base primaquine had no influence on this distribution while at the same time uptake of iron via the transferrin receptor was inhibited. Using immunoelectron microscopy 5'-nucleotidase was found on the cell surface, in multivesicular endosomes and the Golgi complex. Preincubation of the cells in the presence of cycloheximide caused a reduction of labelling in the Golgi complex, whereas the label in the other compartments was retained. These results lead to the conclusion that 5'-nucleotidase does not recycle through the Golgi complex and that in contrast to the transferrin receptor the recycling of 5'-nucleotidase is not inhibited by primaquine.
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PMID:Recycling of 5'-nucleotidase in a rat hepatoma cell line. 285 Jan 62

This study determined whether a single 60-mg dose of ferrous sulfate interferes with fractional zinc absorption (FZA) at 7-9 wk of lactation. In a crossover design, 5 exclusively breast-feeding women were given either a single 60-mg iron supplement or no supplement. FZA was measured by analyzing zinc stable isotope tracers ((70)Zn and (67)Zn) in urine samples collected for 7 d after isotope dosing. A 0.7-micromol intravenous (IV) infusion of (70)Zn as ZnCl(2) in saline was followed by a 0.03-mmol oral dose of (67)Zn as ZnCl(2) given with a standardized meal. After a 7-d wash-out period, the supplement given was reversed and a second FZA measurement was taken. FZA was calculated from isotopic enrichments in urine measured by inductively coupled plasma mass spectrometry. Hemoglobin, plasma ferritin and transferrin receptor, and plasma 5'-nucleotidase, plasma zinc and erythrocyte zinc did not differ before the two measurements of zinc absorption. When women were given a single iron supplement, FZA was significantly lower, 21.7 +/- 1.7% compared with 26.9 +/- 2.6% when no supplement was given (P = 0.032). A single 60-mg iron dose significantly decreases FZA during early lactation.
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PMID:A single 60-mg iron dose decreases zinc absorption in lactating women. 1209 67