RT Journal Article SR Electronic T1 Hippocampus has lower oxygenation and weaker control of brain blood flow than cortex, due to microvascular differences JF bioRxiv FD Cold Spring Harbor Laboratory SP 835728 DO 10.1101/835728 A1 K. Shaw A1 L. Bell A1 K. Boyd A1 D.M. Grijseels A1 D. Clarke A1 O. Bonnar A1 H.S. Crombag A1 C.N. Hall YR 2019 UL http://biorxiv.org/content/early/2019/11/08/835728.abstract AB The hippocampus is essential for spatial and episodic memory but is damaged early in Alzheimer’s disease and is very sensitive to hypoxia. Understanding how it regulates its oxygen supply is therefore key for designing interventions to preserve its function. However, studies of neurovascular function in the hippocampus in vivo have been limited by its relative inaccessibility. Here we compared hippocampal and visual cortical neurovascular function in awake mice, using two photon imaging of individual neurons and vessels and measures of regional blood flow and haemoglobin oxygenation. We show that blood flow, blood oxygenation and neurovascular coupling were decreased in the hippocampus compared to neocortex, because of differences in both the vascular network and pericyte and endothelial cell function. Modelling oxygen diffusion indicates that these features of the hippocampal vasculature could explain its sensitivity to damage during neurological conditions, including Alzheimer’s disease, where the brain’s energy supply is decreased.