pericyte; Rouget cell; mural cell; perithelial cell; adventitial cell

Introduction

One of slender connective tissue cells in close relationship to the outside of the capillary wall.

Function

• contractile cells that wrap around endothelial cells lining capillaries & venules
• they communicate with endothelial cells by direct contact & paracrine signaling
• in the brain, pericytes help sustain the blood-brain barrier
• component of the neurovascular unit
• pericytes regulate capillary blood flow, clearance & phagocytosis of cellular debris, & permeability of the blood-brain barrier
• pericytes stabilize & monitor maturation of endothelial cells
• pericytes are responsible for tight junction formation & vesicle trafficking among endothelial cells
• soluble PDGFR-beta is a CSF biomarker of blood-brain-barrier associated capillary mural cell pericyte function

Structure

• pericytes & endothelial cells share a basement membrane where a variety of intercellular connections are made
• pericyte project finger-like extensions that wrap around the capillary wall, allowing them to regulate capillary blood flow
• pericytes can also form direct connections with neighboring cells via gap junctions

Comparative biology

• pericyte degeneration disrupts white-matter microcirculation, resulting in accumulation of fibrin deposits from the blood, ischemia, loss of myelin, axons & oligodendrocytes, initiating leukoaraiosis

More general terms

• connective tissue cell

Additional terms

• capillary