Microglial conditioned medium promotes survival and development of cultured mesencephalic neurons from embryonic rat brain.
We previously reported that microglial conditioned medium (Mic-CM) has a neurotrophic effect on cultured rat neocortical neurons [Nakajima et al. (1989): Biomed Res 10:411-423]. In order to investigate the interaction between microglia and neurons in more detail, we determined the effects of Mic-CM on the primary cultured mesencephalic neurons from 16-day embryonic rats. The addition of Mic-CM to the culture medium significantly enhanced the survivability of neurons and promoted neurite extension in a low cell-density culture condition. In a high cell-density culture condition, Mic-CM markedly increased dopamine uptake, which was quantified by assessing the specific [3H]dopamine uptake, and also increased the dopamine content of cultured cells. Furthermore, the number of mesencephalic dopaminergic neurons, which was determined by quantitative analysis of tyrosine hydroxylase (TH)-immunoreactive cells, increased significantly in the presence of Mic-CM. These results suggest that Mic-CM enhances survival or maturation of TH-positive neurons present in cultures of the embryonic mesencephalon and that these neurotrophic effects may be due to a diffusible factor(s) from microglia.
Nagata
K
K
Department of Neurochemistry, National Institute of Neuroscience, Tokyo, Japan.
Takei
N
N
Nakajima
K
K
Saito
H
H
Kohsaka
S
S
D000818:Animals; D001921:Brain / Q000166:cytology / Q000196:embryology*; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D002540:Cerebral Cortex / Q000166:cytology / Q000378:metabolism; D017077:Culture Media, Conditioned; D004298:Dopamine / Q000378:metabolism / Q000502:physiology; D005260:Female; D005904:Glial Fibrillary Acidic Protein / Q000378:metabolism; D007150:Immunohistochemistry; D008636:Mesencephalon / Q000166:cytology / Q000502:physiology*; D009457:Neuroglia / Q000502:physiology*; D009474:Neurons / Q000378:metabolism / Q000502:physiology*; D011247:Pregnancy; D051381:Rats; D014446:Tyrosine 3-Monooxygenase / Q000378:metabolism
D017077:Culture Media, Conditioned; D005904:Glial Fibrillary Acidic Protein; D014446:Tyrosine 3-Monooxygenase; D004298:Dopamine