Vagal blood volume receptors compensate for haemorrhage and posture change

Abstract Cranial nerves densely innervate the heart and vasculature, with sensory neurons reporting on blood pressure, respiratory gases and tissue damage 1 . The roles of arterial baroreceptors in systemic physiology are well appreciated 2 , but the functions of vagal cardiac mechanoreceptors have been more difficult to parse, in part due to the closed-loop structure of the cardiovascular system. Here we use genetic tools in mice to identify a small group of neurons that are acutely sensitive to circulating blood volume and initiate a reflex that compensates for decreased filling of the heart in an upright posture and haemorrhage. Vagal PIEZO2 neurons form characteristic end-net endings in the heart, lower…