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URL of this page: //medlineplus.gov/ency/imagepages/19194.htm
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 4/25/2026
Updated by: Diane M. Horowitz, MD, Rheumatology and Internal Medicine, Northwell Health, Great Neck, NY. Review provided by VeriMed Healthcare Network. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.