[Neuroprotective effect of exogenous vascular endothelial growth factor on anoxic rat spinal cord astrocyte and the underlying mechanism].
OBJECTIVE
To observe the effect of hypoxia on primary cultured rat spinal cord astrocyte and investigate the neuroprotective effect of exogenous vascular endothelial growth factor (VEGF) on anoxic astrocyte in vitro.


METHODS
The rat embryonic spinal cord astrocytes were cultured and identified by cellular morphology and glial fibrillary acidic protein (GFAP). The astrocytes were treated with VEGF at different concentrations (10 ng/ml-100 ng/ml) as well as with VEGF receptor (Flk-1) inhibitor SU1498. Then the astrocytes were exposed to hypoxia for different time. The light microscope, MTT assay, TUNEL labeling and SABC immuno-histochemistry were used to measure and observe the changes of the astrocytes in cell morphology, growth, proliferation, GFAP identified that 98% of the purified 1-week cultured cells apoptosis, VEGF and Flk-1 expression.


RESULTS
were astrocytes. 8-12 hours hypoxia obviously induced the activity of astrocyte. The cytobody became bigger, the cytoskeleton grew thicker. The activity of proliferation decreased but apoptosis index increased. The GFAP, VEGF and Flk-1 expression increased. The treatment with 50 ng/ml VEGF 20-24 hours before hypoxia apparently enhanced the activity, decreased the apoptosis index of the astrocytes, and hence improved the hypoxia-injuried astrocytes. Howerver, 700 ng/ml SU1498 obviously inhibited the neuroprotective effect of VEGF on anoxic astrocytes.


CONCLUSIONS
Hypoxia induces reactive activity of astrocyte. The exogenous VEGF exerts neuroprotective effect on astrocytes via VEGF receptor-Flk-1.
Jiang
Shu
S
Department of Neurosurgery, West China Hospital, Sichuan University, Chengdu, China.
Ding
Xin-Min
XM
Mao
Bo-Yong
BY
D000818:Animals; D000831:Animals, Newborn; D001253:Astrocytes / Q000473:pathology*; D015687:Cell Hypoxia / Q000187:drug effects; D002478:Cells, Cultured; D002934:Cinnamates / Q000494:pharmacology; D005904:Glial Fibrillary Acidic Protein / Q000378:metabolism; D018696:Neuroprotective Agents / Q000494:pharmacology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013116:Spinal Cord / Q000473:pathology*; D042461:Vascular Endothelial Growth Factor A / Q000494:pharmacology*; D040301:Vascular Endothelial Growth Factor Receptor-2 / Q000037:antagonists & inhibitors
D002934:Cinnamates; D005904:Glial Fibrillary Acidic Protein; D018696:Neuroprotective Agents; C483044:SU 1498; D042461:Vascular Endothelial Growth Factor A; D040301:Vascular Endothelial Growth Factor Receptor-2