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Regulation of iron entry into reticulocytes

1971; Elsevier BV; Volume: 230; Issue: 2 Linguagem: Inglês

10.1016/0304-4165(71)90225-x

1872-8006

Přemysl Ponňka, Jan Neurwirt,

Neonatal Health and Biochemistry

Abstract 1. 1. All of the tested inhibitors of globin synthesis (puromycin, cycloheximide, emetine, chloramphenicol, tryptamine, NaF, amino acid deficit) decrease reticulocyte radio-iron uptake. Experimental evidence showed that the mechanism of inhibited incorporation of iron into reticulocytes differed according to the inhibitor used. 2. 2. The direct inhibitors of globin synthesis inhibit the membrane transport of iron by a mechanism which depends on the ability of cells to form heme. This is exemplified by estimating the rate of iron uptake by reticulocytes with inhited proteosynthesis which were incubated under conditions of inhibited or restored heme synthesis. Inhibitors of heme synthesis (isonicotinic acid hydrazide or penicillamine) decrease the inhibition of iron uptake caused by cycloheximide, puromycin or emetine. Pyridoxal phosphate, added to reticulocytes incubated with inhibitors of both globin and heme synthesis, was shown to restore heme synthesis which is accompanied by inhibited reticulocyte iron uptake. 3. 3. Experimental evidence is presented that chloramphenicol, tryptamine and NaF inhibit reticulocyte iron uptake by a mechanism which is not directly dependent on the inhibition of globin synthesis. These substances either decrease teh production of energy-rich compounds or damage the cell membrane.