O2-sensitive K+ current in undifferentiated and NGF-treated PC12 cell variants.
It has been reported that cultured PC12 cells can be used as a model for studying mechanisms of O2 sensitivity, previously examined in peripheral chemoreceptors and some neurons. This study compared the hypoxic depression of K+ currents in two PC12 variants, before and after differentiation into neurone-like cells induced by nerve growth factor (NGF). The results show that interaction of O2 and K+ channels is strongly-voltage dependent in the PC12/TM but not the PC12/ES subline. In PC12/TM cells an effect of hypoxia on the K+ current was appreciable only at moderately depolarized voltages, with a loss of sensitivity at +40 to +50 mV. NGF-induced transformation did not affect the responses seen in undifferentiated cells. These results emphasize the importance of screening PC12 cells before selecting a variant for studying O2 sensitivity. In view of evidence cited in the literature that hypoxia may effect membrane channels directly, further molecular and biophysical studies of the differences among PC12 variants are required.
Kawai
Y
Y
Department of Physiology, Faculty of Medicine and Health Science, University of Auckland, New Zealand.
Win
J
J
Comer
A
A
Lipski
J
J
D000818:Animals; D002454:Cell Differentiation; D018492:Dopamine Antagonists / Q000494:pharmacology*; D004353:Drug Evaluation, Preclinical; D014644:Genetic Variation; D006220:Haloperidol / Q000494:pharmacology*; D008564:Membrane Potentials / Q000187:drug effects; D009414:Nerve Growth Factors / Q000494:pharmacology*; D009474:Neurons / Q000187:drug effects / Q000378:metabolism; D010100:Oxygen / Q000494:pharmacology*; D016716:PC12 Cells; D018408:Patch-Clamp Techniques; D015221:Potassium Channels / Q000187:drug effects*; D051381:Rats
D018492:Dopamine Antagonists; D009414:Nerve Growth Factors; D015221:Potassium Channels; D006220:Haloperidol; D010100:Oxygen