liver
Dr.Manuela Mai studied medicine at the Universities of Heidelberg and Mannheim. After graduating, she gained clinical experience in gynecology, pathology and clinical pharmacology. She is particularly interested in the broader connections that lead to diseases - also outside of conventional medicine. She completed additional training in classical homeopathy as well as ear and skull acupuncture.
More about the experts All content is checked by medical journalists.The liver has a lot to offer: Weighing 1.5 kilos or more, the red-brown, multi-lobed structure in the upper abdomen is the heaviest gland in the body. It is one of the largest organs and, as a central metabolic organ, performs tasks that are absolutely vital. Read more about the important organ here: Where is the liver located? What functions does it fulfill? What are common illnesses?
What is the liver?
The healthy human liver is a reddish-brown organ with a soft consistency and a smooth, slightly reflective surface. On the outside it is surrounded by a firm capsule of connective tissue. The average liver weight is 1.5 kilograms in women and 1.8 kilograms in men. Half of the weight is the high blood content of the organ.
The four lobes of the liver
The organ is made up of two large and two small lobes. The two large lobes are called the dexter and sinister lobes (right and left lobes of the liver). The right lobe is significantly larger than the left.
On the underside of the two large lobes are the two small ones: the square lobe (lobus quadratus) and the tail lobe (lobus caudatus). Between them is the porta hepatica (see below).
Eight segments
The liver anatomy not only allows a division into lobes, but - independently of this - also a division into eight segments. This division results from the supply of the individual segments by a bile duct, a portal vein and a liver artery branch. The liver segments work largely independently of one another, so that it is possible, for example, to surgically remove individual segments.
Each segment consists of many one to two millimeters large lobes of the liver that are hexagonal in shape. At the point where three lobules meet, there is a small zone of connective tissue. There is a small branch of the hepatic artery and the portal vein as well as a small branch of the biliary tract. This zone is called the periportal field.
The lobules consist mostly of liver cells (hepatocytes). These have a high metabolic activity and are mainly responsible for liver function.
Porta hepatica
The porta hepatis (porta hepatis) is located on the underside of the large gland. Here blood vessels lead into the organ, while the bile duct (ductus hepaticus) as well as lymph vessels and nerve fibers exit.
The supplying blood vessels are the portal vein (Vena portae) and the hepatic artery (Arteria hepatica).
The latter supplies the organ with oxygen-rich blood. The portal vein, on the other hand, transports the blood loaded with nutrients from the digestive tract.
Does the liver grow back?
The organ has an enormous ability to regenerate: about half a donor liver per patient is sufficient for transplants. In the donor and in the recipient, the respective halves of the organ begin to grow after a few days. The gland returned to its original size within two months.
What is the function of the liver?
The liver is the central metabolic organ and fulfills many vital tasks:
Nutrient juggler
The intestine absorbs sugar, fatty acids, vitamins & Co. from the food pulp and sends them to the liver via the portal vein. This removes excess nutrients that are currently not needed in the body from the blood and stores them. If any part of the body (such as the brain) registers a need for certain nutrients, the storage organ releases them again and feeds them into the bloodstream.
Recycling and garbage disposal
The most diverse metabolic products are converted and broken down in the hepatocytes. What is unusable is disposed of by the metabolic organ either via the kidneys (water-soluble substances) or - packed in the bile (see below) - via the intestine (fat-soluble substances).
High performance filter
The hepatocytes filter out old hormones and blood cells, bacteria and defective cells from the blood. Pollutants such as ammonia (from the breakdown of protein), alcohol, pesticides and plasticizers as well as medicines are disposed of by the liver, which is a detoxification organ.
Hormone factory
The liver produces growth hormones, releases the hormone-like vitamin D, and can convert thyroid hormones and steroid hormones (such as estrogen).
Gallen mixer
Up to one liter of bile for fat digestion is mixed together in the liver every day and transported to the gallbladder or directly to the duodenum for storage.
Cholesterol supplier
Cholesterol is the starting material for important hormones and the bile acids as well as a component of cell membranes. The body gets a small part of the cholesterol it needs from food. He produces most of the rest himself, in the liver.
Body pharmacy
The liver provides clotting factors that ensure that a small cut does not lead to life-threatening blood loss (blood clotting).
High performance machine
How efficiently the liver fulfills its tasks is shown by the following figures: 1.4 liters of blood flow through the organ every minute. That makes around 2,000 liters of body juice per day, which around 300 billion hepatocytes filter, detoxify, remove excess nutrients or load with necessary nutrients and then release them back into the circulation.
Where is the liver located?
Most of the liver is located in the right upper abdomen, directly below the diaphragm, and its left edge protrudes far above the stomach. It is protected by the bony rib cage. On the upwardly curved surface, it is covered by the peritoneum, i.e. it lies in the abdominal cavity (intraperitoneally).
The lower surface of the wedge-shaped organ borders on various abdominal organs - the right kidney and adrenal gland, the duodenum, stomach and large intestine, the gallbladder, pancreas and spleen and the small intestine.
The liver is fused with the underside of the diaphragm. It therefore shifts downwards with every inhalation and can be felt under the right costal arch in healthy people when inhaling deeply. When you exhale, the large gland with the diaphragm is pulled slightly upwards.
The metabolic organ is also attached to the abdominal wall by several ligaments and connected to the stomach and duodenum.
What problems can the liver cause?
The tasks of the liver are very diverse, which is why diseases or injuries to the organ often have very serious health consequences. Despite its high regenerative capacity, the large gland can be so badly damaged (for example by alcohol, medication or illness) that it can no longer (adequately) fulfill its tasks.
Common diseases are, for example, inflammation of the liver (hepatitis) and cirrhosis of the liver. Hepatitis can be acute or chronic and have different causes. Mostly a virus infection is behind it. For example, hepatitis A, B and C are caused by different types of viruses.
In cirrhosis, the functional tissue of the gland is slowly and irrevocably replaced by connective tissue, which, however, cannot fulfill the organ's various tasks. Possible causes of cirrhosis are, for example, alcohol abuse, viral infections and hereditary metabolic diseases.
Doctors speak of fatty liver when the fat content in the hepatocytes is excessively high. Possible causes for this are obesity, alcohol and drug abuse.
Liver cancer (carcinoma) is a relatively rare cancer that predominantly affects men. The malignant tumor usually originates from the hepatocytes (hepatocellular carcinoma), sometimes also from the bile ducts running in the organ (cholangiocellular carcinoma) or blood vessels (angiosarcoma).
Autoimmune liver diseases include autoimmune hepatitis, primary biliary cirrhosis (PBC) and primary sclerosing cholangitis. PBC is a chronic inflammation of the biliary tract with an unknown cause. In primary sclerosing cholangitis, the middle and larger biliary tract in the liver is inflamed. In addition, many patients suffer from the chronic inflammatory bowel disease ulcerative colitis.
Typical side effects of the diseases mentioned can be tiredness and decreased performance, itching, pain under the right costal arch, nausea and vomiting, and impaired blood clotting and jaundice (jaundice). The latter is caused by an increase in the bile pigment bilirubin in the blood.
If the central metabolic organ can no longer fulfill its tasks, there is danger to life. Such failure of the liver can occur acutely or develop chronically.
Tags: travel medicine interview Menstruation
