Effects of 10−8 M captopril (CPT,
(a) and (b)), zofenoprilat (ZOF,
(a) and (c)), lisinopril (LIS,
(a) and (d)), enalaprilat (ENA,
(a) and (e)), and bradykinin (BK,
(a) and (f)) on nitric oxide production, as evaluated by nitrite plus nitrate
concentrations in culture medium (expressed as % of control) by vascular
endothelial cells derived from umbilical cord vein after 8 hours of incubation
both alone and in the presence of either Des-Arg9-[Leu8]-BK,
that is, a bradykinin B1 receptor antagonist (B1ra, 10−6 M), or D-Arg-[Hyp3, Thi5,8, D-phe7]-BK,
that is, a bradykinin B1 receptor antagonist (B2ra, 10−6 M), or the NO synthase competitive inhibitor Nω-nitro-L-arginine methyl ester (L-NA,
3 × 10−3 M). (A) P < .0001 versus control; (B) P < .02
or less versus CPT, LIS, ENA, and BK and P < .0001 versus control; (C) P < .0003
or less versus control, CPT+B2ra and CPT+L-NA; (D) P < .0001 versus
control and ZOF+L-NA and P < .003 versus ZOF+B2ra; (E) P < .003
versus control and ZOF+L-NA; (F) P < .0004 or less versus control,
LIS+B2ra and LIS+L-NA; (G) P < .0006 or less versus control, ENA+B2ra
and ENA+L-NA; (H) P < .0001 versus control, BK+B2ra and BK+L-NA.