Body understands what are the ways to regulate and monitors its blood pressure. There are special sensors in the walls of the arteries and heart that can feel blood pressure. Such special sensors are known as baroreceptors. Baroreceptors sense Blood Pressure and afterward send signals to the kidneys, the arterioles, the heart and the veins which force them to bring in changes which lower or increase blood pressure. Blood pressure adjustment is performed in many ways.:

The ejection of blood will be more with each shrinking if heart increases speed and contracts more frequently. Such two responses increase the blood flow into the arteries & raise BP.

The veins could contract and expand. Whenever enlargement movt is done more blood get stored in the veins and the heart could not have enough amount of blood. Finally BP gets less as heart pumps less blood. But, When and if the veins contract, less amount of blood get stored in the veins, more blood comes back to Heart for pumping into the arteries, &, therefore, the heart give out more and more blood and BP is elevated.

The arterioles may contract and expand. In case arterioles expand blood pressure reduces due to less resistance to the blood flow & when arterioles shrink blood pressure boosts due to more resistance to the flow of blood.

By increasing or decreasing the amount of urine even kidney may inform you about the changes in your blood pressure. The urine is basically water which is taken out from blood so that if a kidney creates additional urine, amount of the blood that fulfills the veins and the arteries lessens, & it reduces BP.