Dietary vitamin e supplementation attenuates hypertension in Dahl salt-sensitive rats

J Cardiovasc Pharmacol Ther. 2005 Jun;10(2):103-11. doi: 10.1177/107424840501000204.

Abstract

There is strong evidence that excess dietary salt (NaCl) is a major factor contributing to the development of hypertension. Salt-sensitive humans and rats develop hypertension even on a normal-salt diet. Salt sensitivity is associated with glucose intolerance and insulin resistance in both humans and animal models, including Dahl salt-sensitive (DSS) rats. In insulin resistance, impaired glucose metabolism leads to elevated endogenous aldehydes that bind sulfhydryl groups of membrane proteins, altering calcium channels, and increasing cytosolic free calcium ([Ca2+]i) and blood pressure. Vitamin E lowers tissue aldehyde conjugates, cytosolic [Ca2+]i, and blood pressure in spontaneously hypertensive rats and fructose-induced hypertensive Wistar Kyoto rats, models of insulin resistance. This study investigated the effect of a normal-salt diet on tissue aldehyde conjugates, cytosolic [Ca2+]i, and blood pressure in DSS rats and the effect of vitamin E supplementation on blood pressure and associated biochemical changes in these animals. Seven-week-old DSS rats were divided into 3 groups of 6 animals each and treated for 6 weeks with diets as follows: low-salt (0.4% NaCl); normal-salt (0.7% NaCl) and normal salt (0.7% NaCl) plus vitamin E (34 mg/kg feed). At completion, animals in the normal-salt group had significantly elevated systolic blood pressure, cytosolic [Ca2+]i, and tissue aldehyde conjugates compared with the low-salt group. They also showed smooth muscle cell hyperplasia in small arteries and arterioles of the kidney. Dietary vitamin E supplementation significantly attenuated the increase in systolic blood pressure and associated biochemical and histopathologic changes.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aldehydes / metabolism
  • Animals
  • Antioxidants / pharmacology*
  • Antioxidants / therapeutic use
  • Blood Platelets / drug effects
  • Blood Platelets / metabolism
  • Blood Pressure / drug effects
  • Body Weight / drug effects
  • Calcium / metabolism
  • Dietary Supplements*
  • Disease Models, Animal
  • Eating / drug effects
  • Hypertension / drug therapy*
  • Hypertension / pathology
  • Hypertension / physiopathology
  • Organ Size / drug effects
  • Rats
  • Rats, Inbred Dahl
  • Vitamin E / pharmacology*
  • Vitamin E / therapeutic use

Substances

  • Aldehydes
  • Antioxidants
  • Vitamin E
  • Calcium