FIGURE 3.

Schematic representation of the effects of astrocytes on bAVM pathogenesis. Astrocytes express mGluR and P2YR which interact with glutamate or ATP. Activation of these receptors trigger IP3 signaling cascade and the intracellular calcium currents, leading to the release of vasoactive molecules. These agents finally contribute to neurovascular coupling. Astrocytes also release VEGF in bAVM, which delivered to the ECs enhancing angiogenesis. Astrocytes also express CYR61, which takes part in angiogenesis. Foot processes of astrocytes express integrin αvβ8, interacting with LAP and activates TGF-β which promotes differentiation and maintenance of vessels. ECs: endothelial cells, mGluR: metabotropic glutamate receptors, P2YR: purinergic receptors, ATP: adenosine triphosphate, LAP: latency-associated peptide, IP3: inositol triphosphate.