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Updated: May 10, 2026

Microperfusion Technique to Investigate Regulation of Microvessel Permeability in Rat Mesentery
Published on: September 12, 2015
Are the precapillary sphincters and metarterioles universal components of the microcirculation? An historical review
Tatsuo Sakai1, Yasue Hosoyamada
1Department of Anatomy and Life Structure, Faculty of Medicine, Juntendo University, 2-1-1 Hongo, Bunkyo-ku, Tokyo 113-8421, Japan. tatsuo@juntendo.ac.jp
Abstract:
The microcirculation is a major topic in current physiology textbooks and is frequently explained with schematics including the precapillary sphincters and metarterioles. We re-evaluated the validity and applicability of the concepts precapillary sphincters and metarterioles by reviewing the historical context in which they were developed in physiology textbooks. The studies by Zweifach up until the 1950s revealed the unique features of the mesenteric microcirculation, illustrated with impressive schematics of the microcirculation with metarterioles and precapillary sphincters. Fulton, Guyton and other authors introduced or mimicked these schematics in their physiology textbooks as representative of the microcirculation in general. However, morphological and physiological studies have revealed that the microcirculation in the other organs and tissues contains no metarterioles or precapillary sphincters. The metarterioles and precapillary sphincters were not universal components of the microcirculation in general, but unique features of the mesenteric microcirculation.
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