The neurovascular unit in brain function and disease

• Published in: Acta Physiologica Vol. 203; no. 1; pp. 47 - 59
• Main Authors: Lecrux, C., Hamel, E.
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Oxford, UK Blackwell Publishing Ltd 01.09.2011; Wiley-Blackwell
• Subjects: Alzheimer's disease; Animals; Astrocytes; Astrocytes - physiology; Biological and medical sciences; Blood; Brain - blood supply; Brain - physiology; Brain mapping; cerebral blood flow; Cerebrovascular Circulation - physiology; Communication; Energy; Functional magnetic resonance imaging; Fundamental and applied biological sciences. Psychology; GABA interneurons; Hemodynamics; Hemodynamics - physiology; Humans; in vivo pharmacology; Neurodegenerative diseases; Neurodegenerative Diseases - physiopathology; Neuroimaging; Neurons; Neurons - physiology; neurovascular coupling; Oxygen; Positron emission tomography; pyramidal cells; Vertebrates: anatomy and physiology, studies on body, several organs or systems; Regional blood flow; Nervous system diseases; Neuroglia; Central nervous system; neurovascular coupling; pyramidal cells; Astrocyte; Encephalon; Interneuron; Cerebral disorder; GABA interneurons; In vivo; Vertebrata; Mammalia; Central nervous system disease; Neurotransmitter; GABA; cerebral blood flow; Hemodynamics; astrocytes; Pyramidal neuron; in vivo pharmacology
• ISSN: 1748-1708; 1748-1716
• DOI: 10.1111/j.1748-1716.2011.02256.x

Neurovascular coupling, or functional hyperaemia, refers to complex mechanisms of communication between neurons, astrocytes and cerebral vessels which form the neurovascular unit that spatially and temporally adjusts blood supply to the needs in energy and oxygen of activated neurons. Neurovascular coupling is so precise that it underlies neuroimaging techniques to map changes in neuronal activity. Therefore, understanding its basis is indispensable for the proper interpretation of imaging signals from functional magnetic resonance imaging and positron emission tomography, routinely used in humans. Although neurovascular coupling mechanisms are not yet fully understood, considerable progress has been made over the last decade. In this review, we present recent knowledge from in vivo studies on the cortical cellular network involved in neurovascular coupling responses and the mediators implicated in these haemodynamic changes. Recent findings have emphasized the intricate interplay between both excitatory and inhibitory neurons in neurovascular coupling, together with an intermediary role of astrocytes, which are ideally positioned between neurons and microvessels. Finally, we describe latest findings on the alterations of neurovascular function encountered in neurodegenerative conditions such as Alzheimer’s disease.