γ-Tocopherol Enhances Sodium Excretion as a Natriuretic Hormone Precursor

Autor: UTO, Harumi, KIYOSE, Chikako, SAITO, Hisako, UEDA, Tadahiko, NAKAMURA, Takaharu, IGARASHI, Osamu, KONDO, Kazuo
Jazyk: angličtina
Rok vydání: 2004
Předmět:
Zdroj: Journal of nutritional science and vitaminology. 50(4):277-282
ISSN: 0301-4800
Popis: application/pdf
学術雑誌論文
Endogenous natriuretic factors are believed to be responsible for extracellular fluid homeostasis in mammals. A new endogenous natriuretic factor, Loma Linda University-alpha (LLU-α) has recently been proven to be a 2,7,8-trimethyl-2-(2'-carboxyethyl)-6-hydroxychroman (γ-CEHC), which is a metabolite of γ-tocopherol (γ-Toc). The purpose of this study was to investigate whether γ-Toc could accelerate sodium excretion into rat urine as a natriuretic hormone precursor. Male SD strain rats were divided into two groups ; one was a control diet group, while the other was a high NaCl group (50 g/kg diet). Next, the two groups were each subdivided into two groups consisting of a placebo group and a γ-Toc group. After the oral administration of one experimental dose of 20 mg γ-Toc or placebo, rat urine was collected at 6 h intervals for 24 h, and then the urine volume, sodium and potassium and γ-CEHC content were determined. γ-Toc increased in the urine volume of the high-NaCl intake group. The sodium excretion in the high-NaCl group given γ-Toc was 8.29±2.20 g, while in the control group given γ-Toc it was 6.24±1.49 g from 12-18 h. In contrast, the potassium excretion in the rat urine did not change in any of the groups. Our findings suggested that γ-Toc accelerates the degree of sodium excretion in rats with a high sodium intake.
Databáze: OpenAIRE