Isoferritins in rat Kupffer cells, hepatocytes, and extrahepatic macrophages. Biosynthesis in cell suspensions and cultures in response to iron
Cultures of Kupffer cells and of hepatocytes, prepared from single rat livers, synthesized ferritin protein equally efficiently. In culture but not in suspension, both sorts of cells responded significantly to stimulation with iron by increased ferritin synthesis. As determined by isoelectric focusing, the isoferritin profiles of newly synthesized /sup 14/-labeled Kupffer cell and hepatocyte ferritin were identical, each having three bands. However, unlabeled ferritin, extracted from nonparenchymal liver cells (mainly Kupffer and endothelial cells) of iron-loaded rats, contained an acidic isoferritin that was not present in hepatocyte ferritin. Investigation of ferritin synthesis in cultured peritoneal and alveolar macrophages yielded similar results. The isofocusing profile of newly synthesized peritoneal macrophage ferritin was indistinguishable from the profile of fresh Kupffer cell or hepatocyte ferritin. Thus, the three isoferritins common to Kupffer cells, hepatocytes, and extrahepatic macrophages are neither cell- nor tissue-specific. However, modifications on intracellular storage may affect the isofocusing properties. The findings, although consistent with the LnH24-n subunit model of ferritin protein, indicate identical restrictive genomic control of the H:L ratios in these sorts of cells. Further, they make it probable that Kupffer cell ferritin iron, originating by endogenous synthesis, is the principal source of Kupffer cell hemosiderin iron.
- Research Organization:
- Department of Pathology, University of Rochester School of Medicine and Dentistry, New York
- OSTI ID:
- 5428387
- Journal Information:
- Lab. Invest.; (United States), Journal Name: Lab. Invest.; (United States) Vol. 45:6; ISSN LAINA
- Country of Publication:
- United States
- Language:
- English
Similar Records
Extrahepatic synthesis of apolipoprotein E
Local proliferation and extrahepatic recruitment of liver macrophages (Kupffer cells) in partial-body irradiated rats
Related Subjects
550301* -- Cytology-- Tracer Techniques
551001 -- Physiological Systems-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ANIMAL TISSUES
ANIMALS
BIOLOGICAL EFFECTS
BIOSYNTHESIS
BODY
CARBON 14 COMPOUNDS
CELL CULTURES
COMPLEXES
DIGESTIVE SYSTEM
ELEMENTS
FERRITIN
GLANDS
IRON
IRON COMPLEXES
ISOTOPE APPLICATIONS
LABELLED COMPOUNDS
LIVER
MAMMALS
METALLOPROTEINS
METALS
ORGANIC COMPOUNDS
ORGANS
PHYSIOLOGY
PROTEINS
RATS
RETICULOENDOTHELIAL SYSTEM
RODENTS
STIMULI
SYNTHESIS
TISSUES
TRANSITION ELEMENT COMPLEXES
TRANSITION ELEMENTS
VERTEBRATES