New insights into salt-sensitive hypertension.
Salt sensitivity, described as association between salt intake and blood pressure, varies among individuals. HSD contributes to salt-sensitive hypertension. Traditional view on blood pressure regulation was focused on the kidneys and ECV expansion secondary to body Na+ load. However, the latest data suggest that salt-sensitive hypertension does not primarily come about by volume-related mechanisms and other than the renal body fluid control must play an important role. Since Na+ accumulation in the body does not necessarily lead to expansion of the extracellular volume it is suggested that Na+ might be stored in an osmotically inactive form either as osmotically inactive Na+ storage in the skin and/or osmotically neutral Na+/K+ exchange in muscle. Hypertonicity in the skin interstitium compared with blood and therefore osmotic stress may be a crucial cause of interstitial Na+ accumulation and hypertension development. Dietary salt loading increases osmotically inactive skin Na+ storage and polyanionic character of the skin, leading to local hypertonicity. The response to this hypertonic internal environment in the skin interstitium involves MPS-driven and TonEBP-VEGF-C-mediated hyperplasia of lymph capillaries and increased eNOS expression. A decreased osmotically inactive storage capacity for Na+ or reduced osmotically neutral Na+/K+ exchange may predispose to marked volume retention, and therefore to rise in blood pressure.
Department of Pathophysiology, Jagiellonian University Medical College, Krakow, Poland. agata.ziomber@uj.edu.pl.
Agata
A
Ziomber
Department of Pathophysiology, Jagiellonian University Medical College, Krakow, Poland.
Kajetan
K
Juszczak
Department of Pathophysiology, Jagiellonian University Medical College, Krakow, Poland.
Piotr
P
Thor
D000818:Animals; D001794:Blood Pressure / Q000187:drug effects*; D006801:Humans; D006973:Hypertension / Q000209:etiology*; D009997:Osmotic Pressure / Q000187:drug effects*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012867:Skin / Q000737:chemistry*; D017673:Sodium Chloride, Dietary / Q000009:adverse effects* / Q000032:analysis*
D017673:Sodium Chloride, Dietary