Changes in MAP in response to exogenous Ang I, BK, and Ang II in rats treated with various doses of Ac-SDKP or captopril for 3 weeks. Baseline MAP in each group was control, 120±11 mm Hg; Ac-SDKP 400 μg/kg per day, 112±13 mm Hg; Ac-SDKP 800 μg/kg per day, 126±2 mm Hg; Ac-SDKP 1600 μg/kg per day, 123±9 mm Hg, and captopril, 125±6 mm Hg. Ac-SDKP did not affect the MAP response to Ang I, BK, or Ang II. As expected, captopril attenuated the pressor effect of Ang I and potentiated the depressor effect of BK but did not affect the pressor effect of Ang II. This suggests that Ac-SDKP at the doses used does not affect ACE activity in vivo. *P<0.05 vs control.