Chief artery to the rectal mucosa is the which of the following?

• A. Middle rectal
• B. Inferior rectal
• C. Marginal artery
• D. Superior rectal

Answer: (D)

The principal blood supply to the rectal mucosa comes from the superior rectal artery, the terminal branch of the inferior mesenteric artery. This artery provides the main blood flow to the upper rectum and its mucosa, with its branches delivering nutrients to the mucosal and submucosal layers. It also forms anastomotic connections with the middle and inferior rectal arteries, which supply the mid and lower parts of the rectum, respectively. The middle rectal artery arises from the internal iliac and the inferior rectal from the internal pudendal, feeding the mid and lower rectum and the anal canal. The marginal artery is an anastomotic channel along the colon and does not represent the primary supply to the rectal mucosa. Therefore, the superior rectal artery is the correct choice.