Mesothelium

Definition

The mesothelium is a thin layer of specialized epithelial tissue that lines certain internal organs and body cavities, including the heart (pericardium), lungs (pleura), and abdominal organs (peritoneum). It provides a protective, smooth surface facilitating the movement of these organs within their cavities.

Related terms

Epithelial Tissue: A type of tissue that covers body surfaces, lines hollow organs and cavities, and forms glands; it serves as a barrier against injury and infection.

Pericardium: The double-walled sac containing the heart and the roots of the great vessels, lined by mesothelium, which reduces friction between the heart and surrounding structures during cardiac activity.

Pleura: The serous membrane enveloping the lungs and lining the thoracic cavity, consisting of two layers with mesothelium, which facilitates lung expansion and contraction