The effect of lead exposure and serum deprivation on mesencephalic primary cultures

Neurotoxicology. 1997;18(2):331-9.

Abstract

The effect of Pb2+ was studied in embryonic mesencephalic primary cultures that contain neurons and glia. Pb2+ exposure in absence of serum, damaged more efficaciously the cultured cells than Pb2+ exposure in presence of serum. In serum-free medium, Pb2+ elicited mainly necrosis and apoptosis in maximally 13% of the cells in culture. The glial fibrillary acidic protein (GFAP) content was decreased by Pb2+ exposure in serum-containing medium. The abundance of GFAP was also decreased by serum deprivation that was augmented by the addition of 12.5 microM Pb2+ in serum-free medium. A 6h exposure to 6 microM Pb2+ in serum-free medium also lowered the low affinity 3H-D-aspartate uptake. A 6h exposure of mesencephalic cells to 3-25 microM Pb2+ in serum-free medium failed to alter the number of tyrosine hydroxylase- and calretinin-immunoreactive cells, whereas, 50 microM Pb2+ obliterated both cell types. A 6h exposure of cells to 3 microM Pb2+ in serum-free medium decreased 3H-dopamine uptake by 50 % and 12.5 microM Pb2+ obliterated it. Addition of albumin to serum-free medium failed to prevent the Pb2+ -elicited inhibition of [3H]-dopamine uptake suggesting that the serum-afforded delay of cell death may not be due to a removal of reactive Pb2+ by protein/chelate formation but rather to the Pb2+ -scavenging function of glial cells. Serum deprivation may exacerbate the Pb2+ -induced neurotoxicity presumably by impairing the metal scavenging function of astrocytes.

MeSH terms

  • Animals
  • Aspartic Acid / metabolism
  • Calbindin 2
  • Cell Death / drug effects
  • Cells, Cultured
  • Culture Media, Serum-Free
  • Dopamine / metabolism
  • Glial Fibrillary Acidic Protein / metabolism
  • Immunoblotting
  • Immunohistochemistry
  • Lead / metabolism
  • Lead Poisoning / metabolism
  • Lead Poisoning / pathology*
  • Mesencephalon / cytology*
  • Mesencephalon / metabolism
  • Nerve Tissue Proteins / metabolism
  • Oxidation-Reduction
  • Phenotype
  • Phosphopyruvate Hydratase / metabolism
  • Protein Binding
  • Rats
  • Rats, Sprague-Dawley
  • S100 Calcium Binding Protein G / metabolism

Substances

  • Calb2 protein, rat
  • Calbindin 2
  • Culture Media, Serum-Free
  • Glial Fibrillary Acidic Protein
  • Nerve Tissue Proteins
  • S100 Calcium Binding Protein G
  • Lead
  • Aspartic Acid
  • Phosphopyruvate Hydratase
  • Dopamine