Kidney is a vital organ of the human body, its basic function is to generate the urine, so as to remove the body metabolic product and some toxic wastes, and at the same time by the heavy retain moisture absorption function and other useful substances, such as glucose, protein, amino acid, sodium, potassium, sodium bicarbonate, etc., to regulate water and electrolyte balance and maintain the acid-base balance.At the same time, the kidney also has endocrine function, producing renin, erythropoietin, active vitami D3, prostaglandin, kalin, etc., as the degradation site of some endocrine hormones in the body and the target organ of epigenin. These functions of the kidney ensure the stability of the internal environment of the body, so that metabolism can proceed normally.