The ability to do this is called continence , and the loss of this ability is called incontinence. ATP was recently shown to be released from mucosal epithelial cells during distention of the rat colorectum, which stimulates sensory nerves via P2X 3 receptors Wynn et al. As the EAS relaxes, the passage of stool can occur, facilitated by rectal smooth muscle contraction. The lower limit of the anal valves is the pectinate line, below which is a zone termed the pecten. The external sphincter figs. They are capable of executing their function without extrinsic innervation, and sympathetic and parasympathetic nerves act only in a modulatory capacity. References in periodicals archive?
People with faecal incontinence or leakage of faeces can be helped by undertaking special exercises to strengthen the sphincter muscles. With regular practice, the. Anal fissure (fissures) is a very painful condition caused by trauma to the anus and anal canal, which then cuts or tears the anus and anal canal tissue. These tears. anal sphincter (sphincter a´ni) either of two sphincters (the internal and external anal sphincters) that open and close to control evacuation of feces from the anus.