Rabbit Anti-Human Caveolin 1 monoclonal antibody for IHC-P. Caveolae (also known as plasmalemmal vesicles) are 50-100 nm flask-shaped membranes that represent a subcompartment of the plasma membrane. On the basis of morphological studies, caveolae have been implicated to function in the transcytosis of various macromolecules (including LDL) across capillary endothelial cells, uptake of small molecules via potocytosis and the compartmentalization of certain signaling molecules including G protein-coupled receptors. Three proteins, caveolin-1, caveolin-2 and caveolin-3 have been identified as principle components of caveolae.