AB2.H2.5 Lymphatic Capillary
Lymphoid Capillary:
- Lymphatic capillaries, like blood capillaries have only a simple squamous epithelium forming the wall
- Unlike blood capillaries they do not have a basal lamina
- Attached to the outside of the lymph capillary are collagen anchoring fibrils which attach the capillary to surrounding structures
- These are important to maintain the patency of the capillary lumen when there is an oedematous swelling
- In their absence, the pressure of the oedemic fluid in the tissue space would compress the capillary, occluding the lumen and cutting off the means of escape of that fluid
- Lymphatic capillaries are often found as an anastomosing network around an artery
- The pulsations of the artery will compress the thin walled lymphatic capillaries causing the lymphatic fluid within them to be pushed along
- The valves within the capillaries will direct the flow of the lymph
- Related to this association between arteries and lymphatic capillaries, there is often a close association between the arterial supply to a region of the body and the location of the draining lymph nodes draining lymph from that region: they are located at the root of the artery
