7-Dimethyl­amino-2-phenyl-1,2,4-triazolo[1,5-a][1,3,5]triazin-5-amine methanol solvate1

7-Dimethyl­amino-2-phenyl-1,2,4-triazolo[1,5-a][1,3,5]triazin-5-amine crystallized with one mol­ecule of methanol to give the title compound, C12H13N7·CH3OH. The triazolo[1,5-a][1,3,5]triazine heterocyclic core is essentially planar as are both amino groups that are involved in π-electron delocalization with the triazolo[1,5-a][1,3,5]triazine nucleus. The methyl groups of the dimethyl­amino fragment are involved in the formation of weak intra­molecular C—H⋯N hydrogen bonds with the N atoms of the heterocyclic system. The crystal packing is stabilized by inter­molecular N—H⋯N hydrogen bonds between the triazolo[1,5-a][1,3,5]triazine mol­ecules. The methanol solvent mol­ecule also participates in the formation of the crystal structure via inter­molecular O—H⋯N, N—H⋯O and weak C—H⋯O hydrogen bonds, linking the layers of triazolo[1,5-a][1,3,5]triazine mol­ecules

Reduction of neuronal activity mediated by blood-vessel regression in the brain

The brain vasculature supplies neurons with glucose and oxygen, but little is known about how vascular plasticity contributes to brain function. Using longitudinal in vivo imaging, we reported that a substantial proportion of blood vessels in the adult brain sporadically occluded and regressed. Their regression proceeded through sequential stages of blood-flow occlusion, endothelial cell collapse, relocation or loss of pericytes, and retraction of glial endfeet. Regressing vessels were found to be widespread in mouse, monkey and human brains. Both brief occlusions of the middle cerebral artery and lipopolysaccharide-mediated inflammation induced an increase of vessel regression. Blockage of leukocyte adhesion to endothelial cells alleviated LPS-induced vessel regression. We further revealed that blood vessel regression caused a reduction of neuronal activity due to a dysfunction in mitochondrial metabolism and glutamate production. Our results elucidate the mechanism of vessel regression and its role in neuronal function in the adult brain