Back to Search
Start Over
Formation of cobalt protoporphyrin in the liver of rats. A mechanism for the inhibition of liver haem biosynthesis by inorganic cobalt
- Publication Year :
- 1979
-
Abstract
- 1. Treatment of rats with small doses of CoCl2 decreases liver 5-aminolaevulinate synthase (EC 2.3.1.37) activity and impairs incorporation of 5-amino[14C]laevulinate into liver haem. Salts of other metals (cadmium, nickel, manganese and zinc) are all relatively inactive. 2. The dose-response curves obtained for both these effects closely mirror the accumulation in the liver of a compound that is labelled by 5-amino[14C]laevulinate and is unextractable by acetone/HCl. 3. Incorporation of 5-amino[14C]laevulinate into unextractable compound is also obtained in vitro by incubating liver homogenates with label in the presence of cobalt:isotope-dilution experiments show that the radioactivity passes through pools of porphobilinogen and protoporphyrin, but not of haem. 4. The unextractable compound is not covalently bound to protein and possesses the same extraction and spectral properties as authentic cobalt protoporphyrin. 5. It is concluded (a) that cobalt protoporphyrin is readily formed not only in vitro, but also in vivo, and (b) that its formation accounts for the impaired incorporation of 5-aminolaevulinate into haem and may also be responsible for the action of cobalt on 5-aminolaevulinate synthase.
- Subjects :
- Male
Porphyrins
chemistry.chemical_element
Protoporphyrins
Zinc
Heme
Biochemistry
chemistry.chemical_compound
In vivo
Porphobilinogen
Animals
Molecular Biology
ATP synthase
biology
Cell Biology
Aminolevulinic Acid
Cobalt
Rats
chemistry
Liver
Metals
Spectrophotometry
biology.protein
Protoporphyrin
Electrophoresis, Polyacrylamide Gel
Research Article
5-Aminolevulinate Synthetase
Subjects
Details
- Language :
- English
- Database :
- OpenAIRE
- Accession number :
- edsair.doi.dedup.....572ea27e0f9758c530e9b7b897a49374