Renal physiology series: part 7 of 8: renal acidification

Maintenance of a normal body pH is essential to the efficient functioning of many physiologic processes. The body has a number of mechanisms for preventing fluctuations in body pH. Some of these are designed to prevent minute-to-minute pH fluctuations over the course of the day, and others are designed to maintain pH balance from day to day. The kidney plays a key role in both processes. The renal process of bicarbonate reclamation prevents the loss of bicarbonate in the urine, and thus, maintains plasma levels of one substrate that is instrumental to preventing minute-to-minute pH fluctuations. The other renal process, bicarbonate regeneration, replenishes the body's supply of bicarbonate, and thus, maintains pH balance on a day-to-day basis. This article will discuss basic principles of acid-base physiology, the mechanisms designed to prevent fluctuations in body pH, and the renal processes instrumental in maintaining a homeostatic pH environment.