Figure 1. Morphological examination of caveolae in cultured confluent human primary endothelial cells.

Transmission electron microscopy reveals endothelial cells as (A) flat and stretched cells (B) forming closed confluent layers displaying junctional structures (arrow), and caveolae (arrowheads). (C) Caveolae are abundant at the PM, optimally visualized by (D) freeze fracture EM revealing patches of caveolae (arrowheads) in proximity of juntional structures (arrows). Scale bar indicates 100 nm.