Effects of Rut-bpy (Cis-[Ru(bpy)2(SO3)(NO)]PF 6), a novel nitric oxide donor, in L-NAME-induced hypertension in rats.

Purpose: To evaluate the effect of Rut-bpy (Cis-[Ru(bpy)2(SO3)(NO)]PF 6), a novel nitric oxide donor in Nω-nitro-L-arginine methyl ester (L-NAME)-induced hypertensive rats.

Methods: Twenty-four male Wistar rats were randomly assigned to four groups (n=6), named according to the treatment applied (G1-Saline, G2-Rut-bpy, G3-L-NAME and G4-L-NAME+Rut-bpy). L-NAME (30 mg/Kg) was injected intraperitoneally 30 minutes before the administration of Rut-bpy (100 mg/Kg). Mean abdominal aorta arterial blood pressure (MAP) was continuously monitored.

Results: Mean arterial blood pressure (MAP) in G3 rats rose progressively, reaching 147±16 mmHg compared with 100±19 mm Hg in G1 rats (p<0.05). In G4 rats, treated with L-NAME+Rut-bpy, MAP reached 149+11 mm Hg while in G2 rats, treated with Rut-bpy, MAP values were 106±11 mm Hg. In G1 rats these values decreased progressively reaching 87+14 mm Hg after 30 minutes. An important finding was the maintenance of the MAP throughout the experiment in G2 rats.

Conclusion: Rut-bpy does not decrease the MAP in L-Name induced hypertensive rats. However, when it is used in anesthetized hypotensive rats a stable blood pressure is obtained.