The mechanotransduction of blood pressure

Two stretch-activated channels in arteries could be targets for some types of heart failure The arterial baroreceptor reflex is the most important mechanism for minimizing short-term arterial blood pressure fluctuations ( 1 ). In situations of sudden blood pressure drops, the baroreceptor reflex accelerates heart rate, increases cardiac contractility, and induces vasoconstriction. Conversely, sudden increases in blood pressure trigger the opposite response. The autonomic nervous system mediates these physiological reactions. Patients with baroreceptor reflex malfunctions typically suffer from orthostatic hypotension, a severe decrease in blood pressure that occurs when standing up, which leads to dizziness or even fainting ( 2 ). However, how blood pressure changes are converted into electrical signals for neurotransmission has remained a puzzle. On page 464 of this issue, Zeng et al. ( 3 ) show that the mechanosensitive ion channels PIEZO1 and PIEZO2 are transducers of blood pressure in the sensory neurons of the autonomic nervous system that trigger the baroreceptor reflex. Identifying the molecular players of this response may help clarify the role of arterial baroreceptors in maintaining normotension and help develop new drugs for the treatment of heart failure.