Normally about 1/5-1/4 of the blood from the heart will pass through the kidneys and enter the kidneys via the renal artery. The pressure of blood on the kidneys is called renal artery perfusion pressure. Renal artery perfusion pressure is mainly to maintain sufficient blood supply to the kidneys for effective detoxification and drainage. If the patient has vomiting, diarrhea, blood loss, heart failure, shock and other diseases, it will cause the blood pressure to drop, the perfusion of the kidney will be insufficient, the filtration rate of the glomerulus will be reduced, and the patient will have symptoms such as oliguria or even anuria. High perfusion pressure also has certain effects on the kidneys, for example, in the pathogenesis of chronic renal failure, one of the points is that the high perfusion pressure of the kidneys leads to continuous damage to the kidneys. This is the time to apply drugs that reduce the perfusion pressure of the kidneys, mainly valsartan and benazepril such drugs.