Early hypoxia modulates the phenotype of dopaminergic cells in rat di- and mesencephalic cell cultures and induces a higher vulnerability of non-dopaminergic neurons to a second hypoxic exposure.
To investigate long-term effects of hypoxia on a cellular level, di- and mesencephalic cell cultures were exposed to hypoxia on in vitro day 2 (incubation in culture medium, pO2 = 10-20 mmHg, 24 h) and on in vitro day 13 (incubation in an electrolyte solution, pO2 = 10-20 mmHg, 8 h). The numbers of neuron-specific enolase immuno-reactive (NSE-IR) and tyrosine hydroxylase immuno-reactive (TH-IR) neurons and the levels of dopamine, its main metabolites and the spontaneous and potassium-stimulated DA release were determined on DIV 15. Hypoxia on DIV 2 did not affect the numbers of NSE-IR and TH-IR neurons, but increased the dopamine content and dopamine release by about 100% in both di-and mesencephalic cultures. In addition, this hypoxia increased the vulnerability of non-TH-IR neurons to the second hypoxic episode applied during more advanced stages of the culture development on DIV 13. On the contrary, hypoxia exposure did not affect the vulnerability of TH-IR cells.
Husemann
B
B
lnstitute of Laboratory Medicine and Pathobiochemistry, University Hospital Charité, Humboldt University, Berlin, Germany.
Andreeva
N
N
Gao
J
J
Heldt
J
J
Andersson
K
K
Gross
J
J
D000818:Animals; D015687:Cell Hypoxia; D002478:Cells, Cultured; D004027:Diencephalon / Q000166:cytology / Q000196:embryology / Q000378:metabolism*; D004298:Dopamine / Q000378:metabolism*; D000860:Hypoxia / Q000378:metabolism*; D007150:Immunohistochemistry; D008636:Mesencephalon / Q000166:cytology / Q000196:embryology / Q000378:metabolism*; D010641:Phenotype; D051381:Rats; D017208:Rats, Wistar
D004298:Dopamine