Descending colon

ColonDiscendente.png

  [[File:|frameless|alt=]]

Front of abdomen, showing surface markings for liver, stomach, and large intestine

Details
Synonyms
Pronunciation
Carnegie stage
Days
Precursor	Midgut
Gives rise to
Part of

The descending colon is a part of the large intestine. It is located on the left side of the abdomen, extending from the transverse colon to the sigmoid colon. The descending colon plays a crucial role in the digestive system by absorbing water and electrolytes from feces.

Anatomy

The descending colon is a continuation of the transverse colon and extends downward to the sigmoid colon. It is retroperitoneal, meaning it is located behind the peritoneum. The descending colon is approximately 25-30 cm in length.

Blood Supply

The descending colon receives its blood supply from the left colic artery, a branch of the inferior mesenteric artery. Venous drainage is through the inferior mesenteric vein, which drains into the splenic vein and then into the portal vein.

Nerve Supply

The nerve supply to the descending colon is provided by the inferior mesenteric plexus, which contains both sympathetic and parasympathetic fibers. The sympathetic fibers originate from the lumbar splanchnic nerves, while the parasympathetic fibers come from the pelvic splanchnic nerves.

Lymphatic Drainage

Lymph from the descending colon drains into the inferior mesenteric lymph nodes. These nodes are located along the course of the inferior mesenteric artery.

Function

The primary function of the descending colon is to store the remains of digested food that will be emptied into the rectum. It also absorbs water and electrolytes, which helps to form solid stool.

Clinical Significance

Conditions that can affect the descending colon include diverticulitis, colorectal cancer, and inflammatory bowel disease. Symptoms of descending colon disorders may include abdominal pain, constipation, and diarrhea.

See Also

• Large intestine
• Transverse colon
• Sigmoid colon
• Rectum
• Digestive system