IMAGING AND ANALYSIS OF PERIVASCULAR NERVES IN HUMAN MESENTERIC AND CORONARY-ARTERIES - A COMPARISON BETWEEN EPI-FLUORESCENCE AND CONFOCAL MICROSCOPY

Perivascular nerves supplying human arteries can be visualised after i mmunohistochemical staining for a variety of markers. The pattern and density of perivascular nerves vary with region, age and disease. Quan tification of the nerve plexus, which may be performed by image analys is, is a prerequisite to assess differences in nerve density. The use of epi-fluorescence microscopy (EFM) presents difficulties in visualis ing the nerve plexus in certain tissues, which can affect the reliabil ity with which specific staining can be localised and distinguished Fr om non-specific staining. In this study, confocal scanning laser micro scopy (CSLM) was used in parallel with EFM, in order to compare images from both techniques. In a comparison of identical areas of nerve ple xuses of human mesenteric and coronary arteries stained for protein ge ne product (PGP) 9.5 and imaged using CSLM and EFM, higher values for area percent (area occupied by nerves), and intercept density (ID/mm, which reflects the number of nerve bundles detected) were found in CSL M images. Similar comparisons of unmatched epi-fluorescence and confoc al images from a group of 45 mesenteric arteries revealed no significa nt difference for area percent, but significantly higher values for ID /mm in CSLM images, These findings illustrate that the better image qu ality in CSLM influences image analysis and can be very useful in stud ies of dynamic changes in nerve plexuses. We recommend CSLM for tissue s that suffer from high background staining, such as human mesenteric and coronary arteries. (C) 1997 Elsevier Science B.V.