AIM AND METHODSTo investigate DNA strand damage in a model of cerebral ischemia/reperfusion injury in vitro, model of ischemia/reperfusion was produced by incubating the primary neuronal cultures to various durations of hypoxia and glucose deprivation (HGD). DNA single and double strand breaks were detected using PANT and TUNEL staining respectively.

RESULTSA few cell death occurred after 2 h of HGD. Less than 30 percent of cell died after 4 h of HGD, whereas 6-8 h of HGD resulted in cell death in 80 percent of neurons. Neuronal cell death reached the peak 10-18 h after 6 h of HGD, while it took as early as 2 h after 8 h of HGD. Following HGD, PANT positive cells were remarkably increased, which was proportional to the duration of HGD. At 5 minutes after 2, 4, 6 or 8 h of HGD, PANT positive cells were 30%, 50%, 80%, 90% respectively. Meanwhile, no determined in another cultures, DNA double strain breaks were not significantly increased.

CONCLUSIONDNA strain breaks is a very early event of DNA damage following in vitro ischemia/reperfusion, especially DNA single strain breaks.