Metarteriole

Metarteriole is a short vessel that links arterioles and capillaries. In addition to these direct connections to the capillaries, metarterioles are also connected to the venous system via thoroughfare channels and precapillary sphincters.

Structure

Metarterioles are unique in their structure. They have a discontinuous, one-layer thick tunica media, which is different from the continuous two-layer media of arterioles. This unique structure allows them to contract and control the blood flow into the capillaries.

Function

The primary function of metarterioles is to serve as a conduit for blood flow from arterioles to capillaries. However, they also play a crucial role in the regulation of blood flow (perfusion) into the capillaries. This is achieved by the contraction and relaxation of the smooth muscle-like cells in their walls, which changes their diameter and thus controls the amount of blood that can flow through them.

Clinical significance

Abnormalities in the structure or function of metarterioles can lead to various health problems. For example, in conditions such as hypertension and diabetes, the walls of the metarterioles can become thickened, which can restrict blood flow and lead to tissue damage. Furthermore, in conditions such as sepsis and shock, the metarterioles can become excessively dilated, which can lead to a drop in blood pressure and potentially life-threatening complications.

See also

• Arteriole
• Capillary
• Precapillary sphincters

References

<references />

• 
  Metarteriole