RESUMO
Objective To explore the regulatory mechanism of gastrin and motilin on sling fibers and clasp fibers of human lower esophageal sphincter.Methods Muscle strips of the sling and clasp fibers from human lower esophageal sphincter and the circular layers of the esophagus and gastric fundus were obtained from patients with subtotal esophagectomy.Through the isolated tissue tension detection technique and pharmacological method,the concentration-response curves of the strips responding to gastrin and motilin were constructed,from which E_(max)s were derived.Results All strips contracted to gastrin and motilin with different rules and different intensity in a concentration-dependent fashion.Sling fibers' E_(max)value(4.91?(0.95 mN/mm~(2))) to gastrin was significantly higher than clasp fibers'(0.72?(0.14 mN/mm~(2))).Otherwise,in response to motilin,both sling fibers and clasp fibers contracted to motilin intensively(3.61?(0.65 mN/mm~(2))and 2.64?(0.33 mN/mm~(2))).Conclusions The sling fibers and clasp fibers have different responses to gastrin and motilin.