Thrombin is a potent mitogen for rat astroblasts but not for oligodendroblasts and neuroblasts in primary culture.
Astroblasts from brain of newborn rat can survive and even proliferate to some extent in a chemically defined medium containing no other growth factor than insulin, providing they are grown first in the presence of fetal calf serum for at least 4 days (Weibel et al., 1984, Int. J. devl Neurosci. 2, 355-366). We found that thrombin is a potent mitogen for these cells, in vitro. The mitogenic activity of thrombin for astroblasts can be compared to that of the astroglial growth factor on astroblasts. However, in contrast to the bFGF, thrombin does not modify significantly the morphology of the cells and their synthesis of glutamine synthetase, an astroglial marker in rat brain. Some other proteases are also able to stimulate the proliferation of astroblasts, but to a lesser extent than thrombin. Thrombin does not stimulate the proliferation of oligodendroblasts from newborn rat and of neuroblasts from 13-day-old rat embryo. These results suggest that in the central nervous system thrombin might play a role in the induction of astrocyte proliferation after brain injury.
Perraud
F
F
Centre de Neurochimie, Strasbourg, France.
Besnard
F
F
Sensenbrenner
M
M
Labourdette
G
G
D000818:Animals; D000831:Animals, Newborn; D001253:Astrocytes / Q000166:cytology* / Q000187:drug effects; D001921:Brain / Q000166:cytology* / Q000187:drug effects; D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured; D006133:Growth Substances / Q000494:pharmacology*; D009457:Neuroglia / Q000166:cytology*; D009474:Neurons / Q000166:cytology* / Q000187:drug effects; D009836:Oligodendroglia / Q000166:cytology* / Q000187:drug effects; D010447:Peptide Hydrolases / Q000494:pharmacology; D051381:Rats; D013234:Stem Cells / Q000166:cytology* / Q000187:drug effects; D013917:Thrombin / Q000494:pharmacology*
D006133:Growth Substances; D010447:Peptide Hydrolases; D013917:Thrombin