Mesenteric vein

One of the large veins which return blood from the intestines. The inferior (lower) mesenteric vein empties into the splenic vein. The superior (upper) mesenteric vein then joins the splenic vein to create the portal vein which goes to the liver.

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mesenteric vein n either of two veins draining the intestine, passing between the two layers of the mesentery, and associated with the corresponding mesenteric arteries:

a) one that is a continuation of the superior rectal vein, that returns blood from the rectum, the sigmoid colon, and the descending colon, that accompanies the inferior mesenteric artery, and that usu. empties into the splenic vein called also inferior mesenteric vein

b) one that drains blood from the small intestine, the cecum, the ascending colon, and the transverse colon, that accompanies the superior mesenteric artery, and that joins with the splenic vein to form the portal vein called also superior mesenteric vein