What are pericytes and astrocytes?
The BBB is formed by the continuous brain microvascular endothelium, its underlying basement membrane, pericytes that tightly encircle the endothelium, and astrocytes in the surrounding tissue space that extend their cell processes towards the endothelium and insert on the basement membrane [5].
Which barrier is constituted by astrocytes and pericytes?
blood–brain barrier
The blood–brain barrier (BBB) constitutes a neurovascular unit formed by microvascular endothelial cells (ECs), pericytes, and perivascular astrocytes (Hawkins and Davis, 2005).
What do pericytes do in the brain?
Brain pericytes are perivascular cells that regulate capillary function, and this localization puts them in a pivotal position for the regulation of central nervous system (CNS) inflammatory responses at the neurovascular unit.
What are retinal pericytes?
They serve as microvascular stabilizers, are potential regulators of microvascular blood flow and have a central role in angiogenesis, as they for example regulate endothelial cell proliferation. Furthermore, pericytes, as part of the neurovascular unit, are a major component of the blood-retina/brain barrier.
What are pericytes in kidney?
Pericytes are contractile cells embedded within the basement membrane of capillaries, which possess elongated processes that encircle the endothelial wall (1). Renal pericytes are associated with glomeruli and cortical and medullary peritubular capillaries as well as with vasa recta.
What is Transendothelial electrical resistance?
Transepithelial/transendothelial electrical resistance (TEER) is the measurement of electrical resistance across a cellular monolayer and is a very sensitive and reliable method to confirm the integrity and permeability of the monolayer.
What is retinal pericyte?
Pericytes are present around blood vessels in the normal retina. Pericyte dropout is one of the major hallmarks of diabetic retinopathy.
What do astrocytes do?
Astrocytes are the most numerous cell type within the central nervous system (CNS) and perform a variety of tasks, from axon guidance and synaptic support, to the control of the blood brain barrier and blood flow.
Where do astrocytes come from?
Astrocytes are derived from heterogeneous populations of progenitor cells in the neuroepithelium of the developing central nervous system. There is remarkable similarity between the well known genetic mechanisms that specify the lineage of diverse neuron subtypes and that of macroglial cells.
Are pericytes fibroblasts?
Although pericytes have been previously hypothesized to derive from adventitial fibroblasts based on observational data (Rhodin and Fujita, 1989) and are often considered related to fibroblast and smooth muscle cells (Stapor et al., 2014), their lineage relationship to skin fibroblast populations remains to be explored …