Sinusoids

A sinusoid is a small blood vessel that is present in various organs of the body instead of capillaries. In the liver sinusoid, the oxygen-rich blood from the hepatic artery meets the nutrient-rich blood from the portal vein. Known in Latin as vas sinusoideum, it is quite similar to a fenestrated capillary and has discontinuous endothelium that mainly serves the purpose of the mixing of the blood. It is also known as a discontinuous capillary, sinusoidal capillary, or simply a sinusoid. It is present in the liver and functions in a way similar to the fenestrated capillaries. 

The liver sinusoid is known to have a larger caliber than all other capillaries of the body and also comprises a lining the lining of specialised endothelial cells known as Kupffer cells and the endothelial cells of the liver sinusoid, abbreviated as LSEC. The cells mentioned here are porous and mainly serve the purpose of scavenging. This article takes a look at the various important details such as the function and purposes of the sinusoid.

The function of the Kupffer Cells

The Kupffer Cells are an important part of the liver sinusoid, along with the liver sinusoidal endothelial cells, which are more commonly known as LSEC, which is their abbreviation. They mainly serve the purpose of scavenging. The Kupffer Cells can take up and destroy foreign bacteria cells. The gap between the hepatocyte and the liver sinusoid is known as the space of Disse. It needs to be noted that the hepatocytes are the cells of the main parenchymal tissue of the liver. They serve purposes such as the synthesis of protein, storage of protein, the transformation of carbohydrates, and also the synthesis of whole salts, phospholipids, and cholesterol. On the other hand, the space of Disse is a place in the liver which is between a hepatocyte and a liver sinusoid. Defenestration is also known as capillarisation happens when LSECs are lost rendering the sinusoid as an ordinary capillary. This process is also the procedure that precedes the process of fibrosis.

Structure of liver sinusoid

Liver sinusoids are a microvascular structure and this structure can rightly be called unique and dynamic as it is different from all the other capillaries of the human body. It is the main site where the exchange between the blood and the perisinusoidal space takes place.

The main purpose of the liver sinusoid

As mentioned before, the main purpose of the liver sinusoid is to act as the main site of exchange and mixing of nutrient-rich blood and oxygen-rich blood, and then it drains this blood into the central vein. This is one of the best sinusoidal function examples. It is the main active site in the liver where most of the functions take place and thus can be regarded as the most important part of the liver. Thus, the liver sinusoid is an irreplaceable part of the liver.

Spleen: Location, function, and other necessary details

The spleen is an important organ of the body that mainly acts as a filter of the blood. It is very similar in structure to a large lymph node. Concerning red blood cells, that is, Red Blood Cells, and the immune system, it has many important functions which make them irreplaceable. It works by removing old red blood cells and also holds a certain amount of blood as reserve which can be utilised in the case of an emergency such as in case of hemorrhagic shock, and it also works by recycling  iron. When it comes to what quadrant and region the spleen is in, the answer would be that the spleen is present in the red upper quadrant of the abdomen. In size, it is similar to the size of a fist and present in the upper left side of the abdomen and next to the stomach, and behind the left ribs in the human body.

Difference between blood capillaries and liver sinusoid

There is a major difference between the spleen and liver sinusoid which is that sinusoids refer to small, irregularly-shaped blood vessels found in certain organs, most importantly the liver, while capillaries, on the other hand, is the name for any of the fine branching blood vessels, which form a network between the arterioles and venules. This is the main difference between blood capillaries and liver sinusoids. 

Conclusion

Thus, the sinusoid is a very important part of the human body and helps in the proper circulation of blood throughout the body, and also serves its main purpose of mixing oxygen-rich blood and nutrient-rich blood. In various parts and organs of the body, they play an important role in the absence of blood capillaries, and thus, they are an irreplaceable part of the body. They are one of the most important parts of the liver and thus, in the absence of a sinusoid, a human body would stop functioning properly.