seroosakalvoja

Seroosakalvoja (serous membranes) are thin, moist membranes that line certain body cavities and envelop visceral organs. They secrete serous fluid, a lubricating liquid that reduces friction between moving surfaces during activities such as breathing, digestion, and heartbeats. Each serous membrane consists of two layers: a parietal layer that lines the cavity and a visceral layer that covers the organs; the space between is the serous cavity containing serous fluid.

Histologically, serous membranes are formed by a layer of mesothelial cells (simple squamous epithelium) supported by connective tissue. The mesothelium produces the serous fluid, while blood vessels supply nutrients and immune components. The membranes provide a slippery surface that facilitates organ movement and may participate in local immune defense.

The best-known serous membranes are the pleura (around the lungs and inside the chest cavity), the pericardium (around the heart), and the peritoneum (lining the abdominal cavity and covering abdominal organs). They also form specialized surfaces in other areas and help isolate organs, aiding in containment of infections or neoplastic spread.

Clinical relevance varies with fluid changes and inflammation. Abnormal accumulation of serous fluid leads to effusions, such as pleural effusion, ascites, or pericardial effusion. Inflammation of serous membranes, serositis, occurs in conditions like pleurisy, pericarditis, or peritonitis and can cause pain and impaired organ movement. Treatment, when needed, targets the underlying cause and the management of the effusion.