Staining behavior and distribution of elastic fibers in the pig skin dermis

For histological demonstration of elastic fibers in the skin, different investigators use a variety of staining procedures. However, some of these popular methods have produced equivocal results for staining sections of mammalian and human skin. The current study concerned the elastic fiber distribution in the skin of the domestic pig from specimens fixed in four different histological fixatives and subjected to paraffin microtomy at various thickness levels and staining by three commonly used procedures, i.e., aldehyde fuchsin, orcein, and Verhoeff elastic stain. An interconnected elastic fiber network was demonstrated in thick paraffin sections (25-60 |μm), whereas thin sections (5-7 (μm) presented a disrupted or discontinuous fiber profile. All the staining procedures produced satisfactory results on thin sections. For thicker sections, the most satisfactory results were obtained with aldehyde fuchsin procedure after pre- oxidation. Preliminary manual morphometric measurement of elastic fiber density with an eyepiece reticle revealed a significantly greater quantity in thicker sections. The distribution pattern of elastic fibers in this animal model seems to simulate that reported for human skin. For future experimental procedures with pigskin to explore skin expansion, or dermabrasion, thick paraffin sections stained with aldehyde fuchsin method will reveal more meaningful information on elastic fiber distribution and better quantitative estimation.