analzáróizom

The analzáróizom, also known as the anal sphincter, is a ring of muscle surrounding the anal canal. It plays a crucial role in controlling the release of feces from the body. There are two main anal sphincters: the internal anal sphincter and the external anal sphincter.

The internal anal sphincter is an involuntary smooth muscle, meaning it operates automatically without conscious control. It is typically contracted at rest, preventing leakage of stool and gas. Its relaxation is controlled by the autonomic nervous system.

The external anal sphincter is a voluntary skeletal muscle, allowing for conscious control over defecation. This muscle can be consciously tightened to prevent the passage of stool when socially inappropriate or when the urge to defecate is not yet strong enough. It can also be voluntarily relaxed to allow for defecation.

The coordinated action of both the internal and external anal sphincters, along with rectal sensation, is essential for maintaining fecal continence. Problems with these muscles, such as weakness or damage, can lead to fecal incontinence, a condition where there is an inability to control bowel movements. This can be caused by various factors including childbirth, surgery, or neurological conditions.