3-D Microscopy Casts Blood Vessel's Structure in New Light
http://www.scientificamerican.com/gallery_directory.cfm?photo_id=14D2F6BF-9735-DA19-3726BA67C31EEE2B
For decades, scientists have used a technique called confocal microscopy to look at the distribution of proteins within a cell. But in a study published recently in Arteriosclerosis, Thrombosis and Vascular Biology, researchers used the technique in a new way: to investigate how those proteins form structures between cells.
"These are some of the first views of the skeleton of the blood vessel," says Gerald Meininger, a vascular physiology researcher from the University of MissouriColumbia. Previous studies told scientists which proteins were used to build a blood vessel wall, but not how they were arranged in three-dimensional space.
To create the image above, Meininger and his colleague Michael Hill used fluorescent tags to label different components of an arteriole wall; cells are labeled in green, whereas elastina stretchy protein that holds the vascular cells togetheris labeled in red. By taking a series of images with a confocal microscope, which relies on point illumination to eliminate out-of-focus areas, the researchers were able to construct a 3-D view of the blood vessel's architecture.
Using similar techniques, Hill and Meininger have already found that the elastin structure of a blood vessel wall differs between body parts and changes as an organism ages. The researchers hope that their tool will improve the understanding of how structural proteins change when people develop high blood pressure or cardiovascular disease and that, one day, it will lead to new therapeutic devices.