Ischemic damage is one of the most serious problems. The openers of KATP channel have been suggested to have an effect to limit the ischemic damage. However, it is not yet clear how KATP channels of a cell correspond to hypoxic damage. To address
the
question, N2a cells were exposed to two different hypoxic conditions as follows: 6 hours hypoxia followed by 3 hours reperfusion and 12 hours hypoxia followed by 3 hours reperfusion. As the results, 6 hours hypoxic treatment increased
glibenclamide-
sensitive basal KATP current activity (approximately 6.5-fold at 0 ㎷ test potential) when compared with nomoxic condition. In contrast, 12 hours hypoxic treatment induced a relatively smaller change in the KATP current density (2.5-fold at 0 ㎷
test
potential). Additionally, in experiments where KATP channels were opened using diazoxide, the hypoxia for 6 hours significantly increased the current density in comparison to control condition (p < 0.001). Interestingly, the augmentation in the
KATP
current density reduced after exposure to the 12 hours hypoxic condition (p < 0.001). Taken together, these results suggest that KATP channels appear to be recruited more in cells exposed to the 6 hours hypoxic condition and they may play a
protective
role against hypoxia-reperfusion damage within the time range.
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