What Is the Spleen?

The spleen is an important lymphoid organ. It is located in the upper left of the abdominal cavity and has a flat oval shape. It is dark red, soft and brittle. The spleen is located between the gastric fundus and the iliac crest in the left quarter costal region, which is opposite to the 9th to 11th ribs. Under normal circumstances, the lower edge of the left costal arch cannot be touched. The spleen is divided into two sides, the upper and lower edges, and the front and rear ends. The inner surface depression is adjacent to the gastric fundus, left kidney, left adrenal gland, tail of pancreas, and left curvature of the colon, and is called the visceral surface. There is a ditch near the center of the visceral surface, which is where the nerves and blood vessels enter and exit. It is called the spleen hilum. The outer surface is smooth and bulge opposite to , which is called face. There are 2-3 notches in the front of the upper edge, which are called spleen notches. When the splenomegaly is enlarged, the spleen notch remains as a sign of palpation. In the vicinity of the spleen, the gastric spleen ligament and the greater omentum often have dark red, varying sizes, and varying numbers of paraspleens. For splenectomy due to hypersplenism, the paraspleen should be removed together. The spleen belongs to the reticulodermal system and is the largest lymphoid organ in the human body. Its structure is basically similar to that of lymph nodes. It consists of the capsule, trabeculae, and lymphatic tissue. It differs from lymph nodes in that there are no lymph sinuses, but there are a large number of blood sinuses.

The spleen is an important lymphoid organ. It is located in the upper left of the abdominal cavity and has a flat oval shape. It is dark red, soft and brittle. The spleen is located between the gastric fundus and the iliac crest in the left quarter costal region, which is opposite to the 9th to 11th ribs. Under normal circumstances, the lower edge of the left costal arch cannot be touched. The spleen is divided into two sides, the upper and lower edges, and the front and rear ends. The inner surface depression is adjacent to the gastric fundus, left kidney, left adrenal gland, tail of pancreas, and left curvature of the colon, and is called the visceral surface. There is a ditch near the center of the visceral surface, which is where the nerves and blood vessels enter and exit. It is called the spleen hilum. The outer surface is smooth and bulge opposite to , which is called face. There are 2-3 notches in the front of the upper edge, which are called spleen notches. When the splenomegaly is enlarged, the spleen notch remains as a sign of palpation. In the vicinity of the spleen, the gastric spleen ligament and the greater omentum often have dark red, varying sizes, and varying numbers of paraspleens. For splenectomy due to hypersplenism, the paraspleen should be removed together. The spleen belongs to the reticulodermal system and is the largest lymphoid organ in the human body. Its structure is basically similar to that of lymph nodes. It consists of the capsule, trabeculae, and lymphatic tissue. It differs from lymph nodes in that there are no lymph sinuses, but there are a large number of blood sinuses.

Western Medicine Name

spleen

Chinese Medicine Name

spleen

English name

Spleen

Other name

spleen

Affiliated Department

surgical-

Contagious

Contagious

Spleen I. Histological structure:

The parenchyma of the spleen is divided into three parts: white pulp, red pulp and marginal zone. The white pith is composed of dense lymphocytes, and it is the main place for specific immunity in the body. When the antigen invades the spleen and causes a humoral immune response, the number of lymph nodes in the white pulp increases. The red pulp is mainly composed of spleen and blood sinus and splenic cord. The slow blood flow in the red pulp makes the full contact between antigen and phagocytes possible. It is the main place for immune cells to phagocytose. Marginal zone (MZ) is located at the junction of red and white pith. Lymphocytes in this area are thinner than white pith and mainly B cells, but there are more macrophages (M), which capture and recognize antigens in the spleen. And important parts of the immune response.

Spleen II, nerve distribution:

The nerves that dominate the spleen are mainly the fibers of the sympathetic ganglion of the abdominal cavity, which enter the spleen with the splenic arteries through the splenic hilum. In addition to the distribution of cholinergic nerves with the vasculature, the spleen tissue is also distributed in the parenchyma and is distributed in nerves of different structures. The fibers are interconnected. The influence of the spleen sympathetic nerve on the immune function of the spleen is mainly manifested in two aspects: regulating the blood flow of the spleen and the function of the spleen immune cells. The electrophysiological activity of the spleen sympathetic nerve is in a dose-dependent relationship with endotoxin. The greater the dose of endotoxin, the higher the intensity of the electrophysiological activity of the spleen sympathetic nerve, the shorter the incubation period, and the lower the blood flow volume of the spleen, indicating that the spleen sympathetic nerve is sensitive to endotoxin. High sex, can quickly adjust the blood flow of the spleen, so that it shows the corresponding immune response. Studies have also found that the impulse release of the spleen sympathetic nerve caused by systemic fever can cause changes in spleen cytokine-related gene expression, of which IL-1 and IL-6 are the most obvious, but the specific effect on immune function is unknown. The nerve fibers of the spleen are undergoing continuous structural remodeling and function reconstruction, which is related to the continuous stimulation of the body, the immune system and the neuroendocrine system continuously feeling stimulation, coordinating functions, responding and regulating.

Spleen III. Physiological Function:

1. The spleen is the "blood bank" of the human body. When the human body is at rest and quiet, it stores blood. When it is under stress such as exercise, blood loss, and hypoxia, it sends blood to the blood circulation to increase blood volume.

2. The spleen is like a "filter". When germs, antigens, foreign bodies, and protozoa appear in the blood, macrophages and lymphocytes in the spleen will eat them.

3. The spleen can also produce immunoglobulins, complements and other immune substances to exert immune effects. The spleen is an important filter in the blood circulation. It can remove foreign bodies, germs, and aging dead cells, especially red blood cells and platelets. Therefore, hypersplenism may cause a decrease in red blood cells and platelets.

4. The spleen also has the function of producing lymphocytes.