β-Galactosidase activity is downregulated by hydrocortisone in 15D3 cells. Confluent 15D3 cells were grown in the absence (top panel) or in the presence (bottom panel) of 10⁻⁶ mol/L hydrocortisone. After 48 hours, cells were fixed with paraformaldehyde and stained for β-galactosidase activity.