FIG. 1.

Growth of HIF-1α-null cells is reduced during hypoxia but not during normoxia. Following overnight seeding at a low density, cells were incubated in normoxic (A) or hypoxic (B) conditions in high-glucose medium and harvested every 24 h until the cultures reached confluence. The average cell number of triplicate plates for each condition ± the SEM was determined by counting by hemacytometer following trypsinization. The maximal difference in growth rates between wild-type (+/+) (⧫) and HIF-1α-null (−/−) (■) cells is noted during hypoxia at 72 h posthypoxia.