A, B) 50 nM ET-1 given for 24 h did not affect NOS1β expression in the mIMCD-3. Pretreatment for 3 h with various doses of the ETA antagonist (A), BQ123, or the ETB antagonist (B), BQ788 also did not affect NOS1β expression. C,D) 24 h, 50 nM ET-1 did not affect NOS3 expression in the mIMCD-3. Likewise, ETA blockade (C) or ETB (D) blockade did not significant affect NOS3 expression. N= 4.