Figure 3.

(a) Concentration–contraction curves for cirazoline in endothelium-denuded pulmonary artery rings from DSR normotensive rats in normal Krebs (NK) plus twice-distilled water (TDW; closed circles), in chloride-free buffer (Cl.Free) plus twice-distilled water (open circles), or from DSS hypertensive rats in normal Krebs plus twice-distilled water (closed triangles), chloride-free buffer plus twice-distilled water (open triangles). (b) Concentration–response curves for methacholine in endothelium-denuded pulmonary artery rings from salt-resistant normotensive (closed circle) or salt-sensitive hypertensive (closed triangles) rats, and concentration–relaxation curves for sodium nitroprusside in endothelium-denuded pulmonary artery rings from salt-resistant normotensive rats (open circles; pD₂=8.4±0.05; n_H=0.76±0.06; n=6; mean±s.e.m.), and salt-sensitive hypertensive (open triangles; pD₂=8.7±0.09; n_H=0.81±0.09; n=6; mean±s.e.m.) in normal Krebs solution. Each point represents a mean of six experiments±s.e.m.