Abstract
Hot springs containing thoron (220Rn), which mainly emits a-rays, are thought to have curing effects on hypertention. We first examined the temporal changes in antioxidants and vasoactive substances in human blood to elucidate the mechanism of alleviation of hypertention by inhalation in the thoron hot spring (6130 Bq/L). Every 2 days, nasal inhalation of vapor from the hot spring in the room was performed for 40 min under a condition of high humidity (90 %). Blood samples were collected after each a bathing on 1 weeks, 2 weeks, and 3 weeks after first bathing, a blood sample also was collected before the first bathing to be used as the control. Results showed that thoron inhalation enhanced the antioxidation function (the increase of catalase activity), and the finding suggestes that thoron inhalation contributes to the prevention of hypertention related to peroxidation reactions. Moreover, the changes in vasoactive substances (dopamine and α-ANP) indicated increase in tissue perfusion brought about by thoron inhalation, suggesting that thoron inhalation plays a role in alleviating hypertention. The findings suggest that an appropriate amount of active oxygen is produced in the body after thoron inhalation, and this contributes to the alleviation of the symptoms of active oxygen diseases such as hypertention.
