What does filling of the lymphatic lumen cause?

Filling of the lymphatic lumen stimulates a reactive contraction of the lymphatic vessels. This contraction is significant as it actively pumps lymph fluid uni-directionally through a system of valves that prevent backflow. The valvular structure within the lymphatic system ensures that once the fluid is propelled forward through contraction, it does not return, maintaining unidirectional flow. This mechanism is crucial for the effective drainage of excess interstitial fluid, cellular waste, proteins, and other substances from tissues back into the circulatory system.

The physiological significance of this process lies in its role in maintaining fluid balance and preventing edema. The active nature of the lymphatic contraction further facilitates the movement of immune cells and waste products, enhancing the body’s ability to respond to infection and tissue repair. This reactive contraction is an essential feature of the lymphatics that distinguishes it from more passive systems of fluid movement.