Figure 3. K5R expression was down-regulated by hypoxia and high glucose. Müller cells were exposed to hypoxia (1% oxygen) or normoxia (20% oxygen) at 37 °C for 12 h. The cells were cultured in high glucose (25 mM glucose) and low glucose (5 mM glucose + 20 mM mannitol) media for 24 h. Total RNA was isolated from the cells and used for real-time RT–PCR of K5R, normalized by the 18s RNA level and expressed as % of respective control (mean±SD, n=3). Values significantly lower than control are indicated (*p<0.05). Hypoxia and high glucose significantly downregulated the expression of the K5R mRNA in cultured Müller cells.