Skip navigation

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

URL of this page: //medlineplus.gov/ency/imagepages/19194.htm

Artery cut section

Artery cut section

Overview

The structure of blood vessel walls is important in the regulation of blood flow. The tunica media contains smooth muscle fibers which contract to either dilate or constrict the size of the vessel. These small changes in the vessel lumen can greatly influence blood pressure and blood flow. Therefore, the tunica media plays an important role in maintaining blood pressure and continuous blood circulation.

Review Date 1/1/2023

Updated by: Michael A. Chen, MD, PhD, Associate Professor of Medicine, Division of Cardiology, Harborview Medical Center, University of Washington Medical School, Seattle, WA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.