The effect of guanylate cyclase inhibitors on non-adrenergic and non-cholinergic neurogenic relaxations of the South American opossum lower esophageal sphincter.

South American (SA) opossum lower esophageal sphincter (LES) circular smooth muscle relaxes by activation of enteric nerves elicited by EFS (electrical field stimulation, 0.5 ms, 48 V, 0.5-8 Hz for 10 s).