TonEBP is a Master Regulator in Protection from Hyperosmolality in the Renal Medulla: Hypertonicity and Urea

ume by osmos C. elegans tol are first allow organic osmol tonicity (28). tonicity allow hypertonicity ic osmolytes o The process expression is i scription facto enhancer bind al regulator fo osmolytes (45 conditions, its ty rises (see be lar accumulati renal medulla membrane cotransperter cotransporter cotransporter enzymes—ald ropathy target glycerophosph 58). The organ sorbitol, and g inside the cel sized because In C. elega encodes glyce key event in th mulation (29) induction of g involved in the form of TonEB there is no To Despite the la sible that the m naling pathwa the stimulatio Urea also ca exceeds 300 m a role in prote by stimulating (HSP70) (49). HSP70 gene in and stimulate gle cell in the TonEBP (4, 30 by gene delet nant negative renal medulla hypertonicity threatening de water via urin ing ability. To medulla, where complex arrangements of tubules, some of which have regulated urea permeability, in combination with dynamics of counter current flow of tubular fluids confer osmotic effectiveness to urea for water reabsorption. In this discussion, however, we will ignore this and define hypertonicity as hyperosmotic salt because we will focus on cellular effects.