Autonomic interactions for control of atrial rate are maintained after SA nodal parasympathectomy

The interactions between the parasympathetic and sympathetic nervous system were analyzed during the chemical disruption or surgical ablation of the ventral right atrial ganglionated plexus (RAGP) in dogs. Dogs that were administered with local injections of hexamethonium or lidocaine attenuated brachycardia which was induced by vagal stimulation. On the other hand, surgical ablation of the RAGP eliminated the direct vagal influence of the sino-atrial node.