Figure 1.

Astrocytic networks are essential to neurovascular units. Astrocytes extend the perivascular processes onto cerebral vascular endothelial cells and pericytes, thereby enwrapping the BBB blood vessels [1, 2]. These astrocytic perivascular processes express integrins that guide and stabilize the endfeet attachments and connexins that support long-range communication in the astrocytic network. Pericytes and endothelial cells express integrins and connexins [3]. Astrocytes extend the perisynaptic processes to the neuronal synapses, thereby surrounding the neuronal synaptic gap, forming a “tripartite synapse” therein [4, 5].