Lymphangionen

Lymphangions are the fundamental functional units of the lymphatic vascular system. They are small, valve-controlled segments of lymphatic vessels. Each lymphangion consists of a sac-like chamber and two valves, one at each end. These valves are crucial for unidirectional lymph flow, preventing backflow and ensuring that lymph moves progressively towards the heart. The contraction of the smooth muscle within the walls of the lymphangion, along with external compression from surrounding tissues and the pressure gradient, drives the movement of lymph. This rhythmic pumping action is essential for the transport of lymph fluid, which contains excess interstitial fluid, proteins, fats absorbed from the digestive system, and immune cells. The coordinated contraction of a series of lymphangions along a lymphatic vessel creates a "lymphangion pump," which is responsible for propelling lymph through the lymphatic network. Disruptions to lymphangion function can impair lymphatic drainage, leading to conditions such as lymphedema. Understanding the structure and function of lymphangions is key to comprehending the overall physiology of the lymphatic system and its role in maintaining fluid balance and immune surveillance.