Abstract

Fe-salicylaldehyde isonicotinoylhydrazone (SIH), which can donate iron to reticulocytes without transferrin as a mediator, has been utilized to test the hypothesis that the rate of iron uptake from transferrin limits the rate of heme synthesis in erythroid cells. Reticulocytes take up 59Fe from [59Fe]SIH and incorporate it into heme to a much greater extent than from saturating concentrations of [59Fe]transferrin. Also, Fe-SIH stimulates [2-14C]glycine into heme when compared to the incorporation observed with saturating levels of Fe-transferrin. In addition, delta-aminolevulinic acid does not stimulate 59Fe incorporation into heme from either [59Fe]transferrin or [59Fe]SIH but does reverse the inhibition of 59Fe incorporation into heme caused by isoniazid, an inhibitor of delta-aminolevulinic acid synthase. Taken together, these results suggest the hypothesis that some step(s) in the pathway of iron from extracellular transferrin to intracellular protoporphyrin limits the overall rate of heme synthesis in reticulocytes.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.