A method for treating a blood vessel in a wall forming a gastrointestinal tract of a body of a mammal. An occlusion is formed in the vessel so as to terminate blood flow to the vessel distal of the occlusion. A method for treating a varix in a gastrointestinal wall, a method of treating an ulcer in a gastrointestinal wall, and a method for treating a hemorrhoid in a rectal wall are also provided.