Blood-brain barrier (BBB) disruption occurs in ageing and is associated with dementia. Endothelial cells and pericytes are closely associated actors of the brain vasculature. Dysfunctions of both cell types have been evidenced in ageing and dementia, though the precise mechanisms leading to BBB disruption are unknown. Vascular basement membrane constitute an acellular interface between these cells, whose degradation on ageing is related to pericyte loss and BBB rupture. In the Montagne Lab, I investigate the interplay between pericytes, vascular basement membrane and endothelial cells in a variety of in vivo and in vitro models, with MRI, electron microscopy, spinning disc confocal and 2-photon imaging.