Skin, dermis and epidermis

This image emphasizes the fibrous connective tissue that comprises the dermis.

Although the difference between the finely-textured collagen of the papillary layer and the coarser collagen fibers of the reticular layer can be fairly distinct, as shown here, the boundary between these two dermal "layers" is fairly arbitrary.

In this H&E stained specimen, collagen appears pink while ground substance is unstained (i.e., the pale background color).  

The very dark purple (nearly black) spots are cell nuclei.  In this location, most of the nuclei belong to fibroblasts.  Some may also belong to macrophages, mast cells, or capillary endothelial cells.  The group of odd-shaped nuclei near the lower right corner belong to neutrophils within a small venule.

Overlying the dermis is the stratified squamous epithelium of the epidermis, consisting primarily of keratinocytes.  

The dark bars across the epidermis that are labelled "artefact" on the image above are wrinkles in the section.

Comments and questions: dgking@siu.edu

SIUC / School of Medicine / Anatomy / David King

http://www.siumed.edu/~dking2/intro/IN033b.htm
Last updated:  23 July 2002 / dgk