[Vascularization of the submucosal and mucosal membranes of the 1st and 2d portions of the duodenum in the adult].

The vascularization of the mucosal and submucosal layers of the first and second duodenal segments of adult man is studied in 12 duodenums, in which the vascular system has been injected with gelatinous india ink. The submucosal layer of the duodenum constitutes a true vascular crossroad of two anastomotic networks, one arterial, the other venous, which morphology is completely superimposable. It differs from the jejunum and the ileum because the existence of the Brünner's glands in the submucosa which are vascularized by an important and characteristic capillary network. The arteries of the mucosa are tributary of the submucosal network. They leave precapillary arterioles which reach the Lieberkühn's glands, the Brünner's gland of the mucosa and the duodenal villi. There, they give rise in three capillary networks which are anastomosed at the base of the villi and within the lamina propria. The venous drainage of the mucosa flows into the submucosal venous network.