Artery, trichrome stain

In this trichrome stained specimen of an artery, collagen is colored blue and smooth muscle is red.  Red blood cells (RBCs) in the arterial lumen are brighter red.  The red texture in the upper-left corner of the image is cross-sectioned smooth muscle in the wall of an (unidentified) organ from which this specimen was taken. 

• The intima is inconspicuous, consisting of little more than very thin endothelial cells.
• Although elastic tissue is unstained in this specimen, the internal elastic lamina can be discerned as a very pale sinuous band between the intima and the media.
• The media is the thickest, most conspicuous layer, in which individual smooth muscle fibers are clearly visible. 
• The adventitia is not a distinct layer but merges with surrounding connective tissue.

Comments and questions: dgking@siu.edu

SIUC / School of Medicine / Anatomy / David King

https://histology.siu.edu/crr/CR038b.htm
Last updated:  22 May 2022 / dgk