rectal valve

anatomy

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July 13, 2026

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Houston's fold, also known as Houston's valve, refers to any of the valvular folds found within the lining of the rectum. These folds are crescent-shaped and are formed by an invagination of the circular muscle and submucosa within the rectal ampulla, which is a dilated section at the end of the rectum. The rectum itself is the final section of the large intestine, terminating at the anus.12

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human digestive system
Rectum and anus
…large crescentlike folds known as rectal valves are located in the rectal ampulla. These valves are caused by an invagination, or infolding, of the circular muscle and submucosa. The columnar epithelium of the rectal mucosa, innervated by the autonomic nervous system, changes to the stratified squamous (scalelike) type, innervated by…
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…large crescentlike folds known as rectal valves are located in the rectal ampulla. These valves are caused by an invagination, or infolding, of the circular muscle and submucosa. The columnar epithelium of the rectal mucosa, innervated by the autonomic nervous system, changes to the stratified squamous (scalelike) type, innervated by…
Read More