Skin, peripheral nerves in dermis

Notes

This image shows connective tissue deep in skin.  

A pair of small peripheral nerves are conspicuous features, along with several small blood vessels and a small amount of subcutaneous adipose tissue.  Fibrous connective tissue of the dermis occupies the remaining area.  

The very dark purple (nearly black) spots are cell nuclei.  At this resolution, they cannot be individually identified except by context.

• Nuclei within the nerves may be either Schwann cells or fibroblasts of the endoneurium.
• Nuclei adjacent to the lumen of a blood vessel belong to vascular endothelial cells.
• Irregular nuclei scattered at random among collagen fibers belong mostly to fibroblasts.  Some may also belong to macrophages, mast cells, or capillary endothelial cells.
• A cluster of lymphocytes appear below the word "axon".

Only the largest, myelinated axons are readily visible in routine light micrographs. Although only a few axons are noticable in the nerves illustrated above, each probably contains scores of smaller axons.

• In skin, large myelinated axons generally serve the sense of touch.  Unmyelinated axons are associated with pain sensation and with autonomic motor function (controlling vascular smooth muscle and sweat glands).

Comments and questions: dgking@siu.edu

SIUC / School of Medicine / Anatomy / David King

http://www.siumed.edu/~dking2/intro/IN013b.htm
Last updated:  25 July 2003 / dgk