What Is the Large Intestine?

The large intestine, which is divided into the cecum, appendix, colon, rectum, and anal canal [1], is an organ that absorbs water from food residues, and the food residues themselves form feces and are excreted to a certain degree. It is an important part of the human digestive system and is the lower part of the digestive tract. The large intestine resides in the abdomen, its upper mouth is connected to the small intestine at the appendix, and its lower end is connected to the anus. The whole process resembles a box, surrounding the jejunum and ileum. The large intestine is significantly different from the small intestine in appearance. Generally, the large intestine has a relatively large caliber and a thin intestinal wall.

The large intestine, which is divided into the cecum, appendix, colon, rectum, and anal canal [1], is an organ that absorbs water from food residues, and the food residues themselves form feces and are excreted to a certain degree. It is an important part of the human digestive system and is the lower part of the digestive tract. The large intestine resides in the abdomen, its upper mouth is connected to the small intestine at the appendix, and its lower end is connected to the anus. The whole process resembles a box, surrounding the jejunum and ileum. The large intestine is significantly different from the small intestine in appearance. Generally, the large intestine has a relatively large caliber and a thin intestinal wall.

Chinese name

the large intestine

Foreign name

large intestine

Including

Colon and rectum

Specific

An important part of the digestive system

Features

Protects mucous membranes and lubricates feces

Pinyin

Da Chang

Large Intestine Anatomy Location

The large intestine resides in the abdomen, its upper mouth is connected to the small intestine at the appendix, and its lower end is connected to the anus. The upper part of the large intestine is called the "ileum" and includes the upper part of the ileum and colon in modern anatomy; the lower part is called the "large bowel" and includes the sigmoid colon and rectum. The large intestine is also an official cavity sexual organ, which is in the form of loops and stacks. It mainly has the physiological functions of transmitting dregs and main nutrients.

Large intestine physiology

1. Main strain of dregs: The large intestine accepts food residues transmitted from the small intestine, absorbs excess water and forms feces. The movement of the large intestine gas transfers feces to the end of the large intestine, and is discharged from the body through the anus in a controlled manner. Therefore, the large intestine is known as the "principal officer".

2. Large intestine: The large intestine receives food residues containing a large amount of water from the small intestine, and absorbs the water in it to form feces, which is the so-called desiccation effect. The large intestine absorbs water and participates in the metabolism of water and fluid in the body.

Large bowel dysfunction

Dysfunction of large intestine conduction dysfunction, abnormal bowel movements, common constipation or diarrhea. If there is a damp and hot stagnation in the large intestine, large intestine conduction dysfunction, abdominal pain, acute aftermath, diarrhea, pus and blood will also appear. Dysfunction of the large intestine, the water in the large intestine must not be absorbed, and water and dregs can cause bowel sounds, abdominal pain, diarrhea and other symptoms. Moisturizing, which will lead to constipation.

Analysis of risk factors of large intestine polyps

A high body mass index increases the risk of colonic polyps, especially in obese patients. A number of foreign studies have found that high BMI increases the risk of intestinal polyps (adenomas, hyperplasia). The possible mechanism is that obesity, especially abdominal obesity, can lead to increased visceral fat and produce insulin resistance and insulin growth factor- An increase in the level of 1 will affect the production of large intestinal polyps by increasing cell proliferation and reducing apoptosis; Foxa2 is activated during insulin resistance and further participates in the conduction of the PI-3K signaling pathway, promoting cell proliferation and causing adenomas. ; Increased inflammatory cytokine precursors and decreased adiponectin production by adipocytes may also lead to the production of large intestinal polyps. Regular drinking is a risk factor for the development of colorectal polyps. The possible cause is that alcohol and its metabolite acetaldehyde can induce DNA methylation, interfere with the absorption of potential anti-cancer nutrients such as folic acid and calcium, and can cause intestinal mucosa. Hyperplasia, these increase the risk of colonic polyps and tumors. And smoking did not increase the risk of intestinal polyps. However, some studies suggest that nicotine in tobacco affects tumor suppressor genes by methylating CPG islands, and eventually affects the occurrence of colorectal polyps and tumors. This may be related to the fact that we did not further stratify the smoking population and the relatively small sample size. High blood lipid levels are a risk factor for the occurrence of large intestinal polyps. Patients with large intestinal polyps have abnormal blood lipids as high as 57.75%. Studies have confirmed that hyperlipidemia can affect the occurrence of colorectal adenomas, especially hypertriglyceridemia and high-density lipoprotein reduction. Fatty acids and triglycerides can trigger inflammatory responses, upregulate the expression of insulin-like growth factor (IGF) and transforming growth factor (TGF), activation of transcription factors such as PPAR, NF-KB, and activation of cyclooxygenase (COX-2) May be the mechanism of hyperlipidemia leading to an increased risk of colorectal polyps. Research on related diseases found that hypertension, diabetes, and history of fatty liver were risk factors for the occurrence of colorectal polyps. The three diseases mentioned above are all closely related to the metabolic syndrome, and hyperinsulinemia and insulin resistance may be the reasons for their susceptibility to colon polyps. At the same time, patients with colorectal polyps with biliary diseases were higher than those in the control group, suggesting that biliary diseases are a risk factor for colorectal polyps. A meta-analysis of biliary diseases and colorectal polyps has been reported by foreign scholars. Of the 42,543 patients with colon adenoma, 28,281 patients had biliary disease or had a cholecystectomy. Biliary diseases may be a sign of visceral autonomic neuropathy, which can lead to gallbladder emptying dysfunction and prolonged intestinal transit time.