Control of vascular tone in the syndromes of Bartter and Gitelman

Bartter's and Gitelman's syndromes can be used as models to gain insight in to the mechanisms responsible for maintaining/controlling vascular tone. In fact, the study of patients with these syndromes provides important insigh ts into mechanistic details of the most relevant pathways of vascular tone. So far, several experimental findings in patients with these syndromes poi nt to G protein abnormalities and suggest that the intracellular signaling systems that involve the G protein complex transducing components may be de fective, leading to altered vascular reactivity. These results are also of particular interest because the derangements found in Bartter's and Gitelma n's syndromes are the mirror images of those involved in the pathophysiolog y of hypertension.