baroreflex

noun

baro·​re·​flex ˈbar-ō-ˌrē-ˌfleks 

: the reflex mechanism by which baroreceptors regulate blood pressure that includes transmission of nerve impulses from the baroreceptors to the medulla in response to a change in blood pressure and that produces vasodilation and a decrease in heart rate when blood pressure increases and vasoconstriction and an increase in heart rate when blood pressure decreases

called also baroreceptor reflex