Pericyte
Pericytes (also pericytes ) are cells that lie against the outer wall of blood capillaries . They belong to the connective tissue cells. They can contract and thereby affect the blood flow to these vessels.
Capillaries are formed by endothelial cells on which pericytes are deposited and which encircle the vessel with appendages; both are connected to one another via gap junctions . Pericytes stabilize the capillary structure and play an important role in the formation of new blood vessels ( angiogenesis ).
It is assumed that damage to pericytes leads to a destabilization of the capillaries and the formation of bulges ( aneurysms ) (e.g. in diabetic retinopathy ). It is also speculated that pericytes are involved in the regulation of the blood supply and in ischemia in the brain, since they can change the capillary diameter by means of contractile proteins ( actin ) in their processes. Electrical stimulation, norepinephrine and ATP act as vasoconstrictors , glutamate dilates .
Individual evidence
- ↑ Ulrich Welsch , Thomas Deller: Textbook Histology . Elsevier , Urban & Fischer, Munich 2010, ISBN 978-3-437-44431-9 , pp. 209 f .
- ↑ C. Peppiatt, C. Howarth, P. Mobbs, D. Attwell: Bidirectional control of CNS capillary diameter by pericytes . In: Nature . tape 443 , no. 7112 , October 2006, p. 700–704 , doi : 10.1038 / nature05193 , PMID 17036005 , PMC 1761848 (free full text).
- ↑ GR Gordon et al: Astrocyte Control of the Cerebrovasculature. In: GLIA. 55, Sep 2007, pp. 1214-1221.