Budget Amount *help |
¥12,300,000 (Direct Cost: ¥12,300,000)
Fiscal Year 1998: ¥4,800,000 (Direct Cost: ¥4,800,000)
Fiscal Year 1997: ¥7,500,000 (Direct Cost: ¥7,500,000)
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Research Abstract |
Sudden death cases, which were considered due to over work or stress, were happened in Asian countries including Japan. Many cases were young males. We have estimated that the hypothesis would be chronic disorder of mineral balance as well as stress. Deficiency of magnesium (Mg) and potassium (K) was paid attention. 1. Mortality rates were observed in male and female mice given Mg and/or K deficient diet. (1) no sexual difference was observed in mice given only Mg deficient diet, (2) in young mice given Mg/K deficient diet, males were died within 2 weeks, while all females were survived, and in 4 month old mice, the mortality curves were shifted 1 week later, (3) in mice received castration and given Mg/K deficient diet, no sexual difference was observed in mortality rate. 2. As the natural results, Mg concentrations were extremely low in various organs of mice fed Mg deficient diet, however, Mg concentration in heart and kidney were kept at the normal ranges. 3. After intravenous injection with stable isotope 26Mg, considerable amount of 26Mg was found in heart and kidney. In heart 26Mg was increasing up to 6 hours. 4. Lipid peroxide and mineral balance were observed in mice housing in the normal conditions (23 C, 60%) or in hot conditions (30 C, 60%) and given normal or Mg/K deficient diet. Lipid peroxide increased in mice housing in hot conditions, and independent from diet. Disorder of mineral balance was appeared in male mice fed Mg/K deficient diet and housing in hot conditions. As conclusion, young male mice were susceptible for Mg and/or K deficiency, and their homeostasis was injured.
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