paksusuolesta

Paksusuolesta is Finnish for the colon, the main section of the large intestine. The colon is located in the abdomen and upper pelvis, stretching from the cecum at the ileocecal junction to the rectum. Its primary roles are absorbing water and electrolytes from indigestible material, forming and storing feces, and housing a large and diverse microbiota. Transit times vary, but the colon typically extracts remaining fluids and passes waste to the rectum for elimination.

Anatomy and histology: The colon is divided into ascending, transverse, descending, and sigmoid segments. It features taenia coli, haustra, and abundant mucous-producing goblet cells. Blood supply comes from the superior mesenteric artery (proximal colon) and inferior mesenteric artery (distal colon), with venous drainage to the portal system. Innervation includes parasympathetic fibers via the vagus nerve to the proximal colon and pelvic splanchnic nerves to the distal colon; sympathetic fibers modulate motility and secretion.

Clinical relevance: Common conditions include colorectal cancer, colorectal polyps, diverticulosis/diverticulitis, and inflammatory bowel diseases such as ulcerative colitis and Crohn's disease when the colon is involved. Screening colonoscopy reduces cancer risk. Dysfunction can manifest as altered bowel habits, abdominal pain, or bleeding. The colon also hosts a dense gut microbiota that contributes to digestion and immune function.