Comparative viability of LSECs cultures maintained under high and low oxygen levels. Cell death was monitored by incorporation of propidium iodide in late apoptotic or necrotic cells in cultures maintained in either high (a) or low (b) oxygen tension. Separately, viability was determined at the indicated time points by MTT colorimetric assay (c). Freshly isolated LSECs cultures were established on 24 well-plates and incubated either at hyperoxia (open bars) or at normoxia (filled bars). The obtained results demonstrate a faster decay of loss of cells in cultures maintained at hyperoxic conditions. Statistical analyses by t-student test: *P < 0.05, **P < 0.001.