The liver is the largest gland in the human body. It plays a very important role in human metabolism, bile production, detoxification, coagulation, immunity, thermogenesis and the regulation of water and electrolyte. It is a huge "chemical factory" in the human body.
First, metabolic function:
① Sugar metabolism: the starch and sugar in the diet are digested into glucose, which is absorbed by the intestine, and the liver synthesizes glycogen and stores it; When the body needs it, liver cells can break down glycogen into glucose for the body to use.
② protein metabolism: the liver is the only synthetic organ of human albumin; Liver is involved in the production, maintenance and regulation of globulin, enzyme protein and plasma protein other than gamma globulin. Amino acid metabolism such as deamination, urea synthesis and ammonia treatment are all carried out in the liver.
③ Fat metabolism: the synthesis and release of fat, the decomposition of fatty acids, the formation and oxidation of ketone bodies, the synthesis of cholesterol and phospholipids, and the synthesis and transportation of lipoprotein are all carried out in the liver.
④ Vitamin metabolism: The synthesis and storage of ABC, D, K and other vitamins are closely related to the liver. Abnormal vitamin metabolism will occur when the liver is obviously damaged.
⑤ Hormone metabolism: The liver is involved in the inactivation of hormones. When the liver function is damaged for a long time, there may be imbalance of sex hormones.
Second, the production and excretion of bile: the intake, combination and excretion of bilirubin, and the production and excretion of bile acids are borne by the liver. Bile produced and secreted by liver cells is transported to gallbladder through bile duct, concentrated and discharged into small intestine to help digestion and absorption of fat.
Third, detoxification: some harmful wastes produced in the process of human metabolism, as well as metabolic decomposition products of foreign poisons, toxins and drugs, are detoxified in the liver.
Immune function: The liver is the largest reticuloendothelial phagocytosis system, which can phagocytize, isolate and remove various invasive and endogenous antigens.
5. Coagulation function: Almost all coagulation factors are made by the liver, which plays an important role in the dynamic balance of human coagulation and anticoagulation systems.
6. Others: The liver participates in the regulation of human blood volume, the generation of heat and the regulation of water and electrolytes.
Spleen has the following four physiological functions:
1. Destroy blood cells: Macrophages in the spleen can devour and destroy aged red blood cells, platelets and denatured white blood cells. It can also devour bacteria, protozoa and foreign bodies in the blood. Hypersplenism can destroy a large number of platelets and blood cells.
2. Blood storage: The spleen is rich in blood sinuses, which can store a certain amount of blood (about 200ml). When the body is vigorously exercising or climbing mountains or suddenly losing blood, the spleen smooth muscle contracts, releasing the stored blood to supplement the body's needs.
3. Hemofiltration: Spleen belongs to reticular skin system and is the largest lymphatic organ in human body. Its structure is basically similar to that of lymph nodes, and it consists of capsule, trabecular bone and lymphoid tissue. It differs from lymph nodes in that there is no lymphatic sinus, but there are a large number of blood sinuses in it, which are filters for blood circulation.
4. Immune function: phagocytosis and elimination of aging red blood cells, bacteria and foreign bodies, production of lymphocytes and monocytes, lymphocytes in the spleen can also produce antibodies.
The function of the stomach mainly includes the following aspects:
(1) The motor function of the stomach can be divided into three types: stirring, peristalsis and tension contraction. Through exercise, food and digestive juice are fully mixed to form chyme, which is sent to the duodenum.
(2) Secretory function of stomach The gastric gland mainly includes parietal cells, main cells and mucus cells. They all have the function of secretion, which can secrete a variety of substances and form the main components of gastric juice.
(3) Gastric mucosal barrier This barrier can prevent sodium ions (Na+) from entering the gastric cavity from the mucosa along the concentration difference, and prevent hydrogen ions (H+) from returning to the mucosa along the concentration difference. Some drugs, such as aspirin, indomethacin, ethanol, etc. Can destroy the gastric mucosal barrier, cause mucosal injury, necrosis, and even ulcer formation.
(4) Cytoprotective effect of gastric mucosa: Gastric mucosal epithelial cells can continuously synthesize and release endogenous prostaglandins, which can prevent or significantly reduce the damage of harmful substances to the mucosa. In addition, some gastrointestinal peptides such as somatostatin also have a certain protective effect on gastric mucosa.
Function of kidney:
(1) renal function
① The kidneys excrete metabolic wastes, and the kidneys have their own regulatory functions. It regulates renal plasma flow through bulb feedback, renal nerves and vasoactive substances, thus keeping the glomerular filtration rate within a certain range.
② The kidney regulates the balance of water and osmotic pressure in the body. Kidney has a strong ability to regulate water excretion according to the needs of the body to maintain the stability of body fluid osmotic concentration.
(3) The kidney excretes and regulates sodium, potassium and chlorine. The kidney is the main excretion place of sodium, potassium and chlorine. The excretion of sodium, potassium and chlorine is directly related to the relative balance of these ions in the body, which is of great significance to maintain the volume, osmotic pressure and acid-base balance of normal body fluids. By regulating the excretion of sodium, potassium and chlorine, it is of great significance to maintain the normal level of potassium, sodium and chlorine in the kidney.
④ When the acid-base balance function of the kidney is normal, the acidic or alkaline substances produced by metabolism will not cause significant changes in blood pH value, mainly because there are a series of regulatory mechanisms in the body, namely: a. Buffer system in body fluids. B. respiratory system. C. kidneys. The regulating function of kidney is slow, but it can completely regulate the pH value of blood.
(2) Endocrine function of kidney
Kidney can produce many bioactive substances, such as renin-angiotensin system, which plays an important role in maintaining normal blood pressure and ion exchange.
The renal tubular epithelium of renal cortex can produce kallikrein, and the collecting duct epithelium can produce kallikrein.
Erythropoietin produced by kidney can transform erythropoietin in blood into erythropoietin, stimulate bone marrow hematopoiesis and accelerate erythropoiesis.
The kidney will also activate vitamin D3, regulate calcium and phosphorus metabolism and promote osteogenesis.
The kidney is also the place where many endocrine substances are decomposed and inactivated, such as parathyroid hormone, gastrin and insulin.