Taurine and the kidneys

The interactions between the kidney and taurine are multifaceted. Taurine contributes to several biologic processes in the kidney, and the kidney influences specific aspects of taurine homeostasis [1]. The numerous molecular and cellular regulators of taurine handling by the kidney have been recently reviewed [2]. Thus, this chapter will examine several aspects of renal function in relation to taurine and will delve into large biologic themes. In addition, the properties of taurine in the pathophysiology of kidney disease will be evaluated. The physiochemical properties of the ß-amino acid taurine are responsible for some of its biologic features. It is readily soluble in aqueous solutions and is not incorporated into protein. Thus, it can serve as an intracellular osmolyte. The taurine molecule acts as a zwitterion at physiologic pH and resides within the cell in millimolar quantities. Its accumulation within the cell requires active uphill transport from the extracellular environment, where it is found in only micromolar quantities [3]. It has the lowest pK1 and pK2 of all amino acids. Some of these properties lead to the role of conjugation of taurine with bile acids [4] and uridine in +RNA [5].