Effects of nerve growth factor on intracellular free Ca2+ in oxygen/glucose-deprived cultures from cerebral cortex of fetal rats
Wu, J.; Zhang, J.
Chinese Medical Journal 111(11): 1031-1034
1998
ISSN/ISBN: 0366-6999 PMID: 11189210 Document Number: 493886
To explore the involvement of calcium in the mechanism of hypoxic/hypoglycemic insults and nerve growth factor (NGF) protection. Neuron viability and lactate dehydrogenase (LDH) efflux in the bathing medium in cerebral cortex cultures from fetal rats were measured. Calcium fluorescent indicator Fura-2/AM was used to measure the intracellular free calcium ([Ca2+]i). Massive neuronal death occurred 16-24 h following the onset of hypoxia/hypoglycemia. NGF (3-100 micrograms.L-1) dose-dependently attenuated 24 h hypoxia/hypoglycemia-induced efflux of LDH and elevated the number of surviving neurons. Hypoxia/hypoglycemia induced a reduction in [Ca2+]i in early stage and a large elevation of [Ca2+]i in later period. NGF 50 micrograms.L-1 increased [Ca2+]i to normal limits during the early stages of hypoxia/hypoglycemia and prevented the later elevation in [Ca2+]i. The [Ca2+]i elevation may be responsible for the cell damage in oxygen/glucose deprived cultures. NGF protects cerebral cortical neurons against hypoxic/hypoglycemic insults via stabilizing [Ca2+]i level or preventing the late rise in [Ca2+]i.