TRANSFORMATION OF MONOCYTES INTO AMEBOID MICROGLIA AND INTO MICROGLIA IN THE CORPUS-CALLOSUM OF POSTNATAL RATS, AS SHOWN BY LABELING MONOCYTES BY CARBON PARTICLES

  • 1 January 1979
    • journal article
    • research article
    • Vol. 128  (JUN) , 847-858
Abstract
This study aimed to clarify the origin of amoeboid microglia (active macrophages) and microglia in the corpus callosum of postnatal brain. Young albino rats, aged 6 days were given, i.v., 2-doses of C suspension at a 24-h interval. The animals were sacrificed at different days after the 2nd C injection. At 1 day after the 2nd injection, C-containing monocytes (carbon-labeled monocyte) were present in the vascular lumina, or penetrating through its wall, or appeared outside the blood vessel in the neuropil of corpus callosum. At 4 and 5 days after the 2nd injection, C particles were observed in amoeboid microglia which were initially unlabeled. At 6 days after the 2nd injection, C particles appeared in some cells which were microglia-like. At 8 and 9 days the 2nd injection, all the C-containing cells were microglia-like. Circulating monocytes are the precursor cells of amoeboid microglia which should eventually become microglia in postnatal brain.