ENDOTHELIAL INJURY IN-VIVO - A TECHNICAL AND STATISTICAL APPROACH TO THE STUDY OF AORTIC INTEGRITY

The endothelium can be a Link connecting risk factors with the develop ment of cardiovascular disease, and methods for studying endothelial i ntegrity are therefore important. We describe a method of studying end othelial injury in vivo by combining immunohistochemistry with an impr oved technique of producing ''en face'' preparations (Hautchens) of ao rtic endothelium of rabbits and guinea pigs. These Hautchens enabled t he study of large numbers of endothelial cells and adherent cells (pro bably leukocytes) at different locations along the aorta. The statisti cal distributions of the number of injured endothelial cells and adher ent cells in a visual field were also investigated, and both closely f ollowed a log-normal distribution. Based on this distribution, a metho d to estimate endothelial injury by grouping the cell count data, inst ead of exact counting, was developed. The grouped cell count data were then used to calculate the grouped mean and grouped standard deviatio n for each animal. The improvements of the technical and statistical m ethods offer good opportunities to study various aspects of endothelia l integrity in a time efficient manner.