Endothelial nitric oxide synthase: from structure to function in one aspartic substitution

Cherney and co-workers examine the functional phenotype of the G894T eNOS polymorphism in a selected group of apparently healthy subjects. The investigators used L-arginine infusion and induced changes in renal hemodynamics. While L-arginine increased effective plasma flow and glomerular filtration rate in GG subjects, these responses were blunted in GT/TT subjects, suggesting that either the G894T polymorphism impairs eNOS function, or GG subjects exhibit augmented eNOS responsiveness to L-arginine. The complexity of this seemingly straightforward conclusion deserves elaboration