BALNEOLOGICAL STUDIES USING RADIOACTIVE ISOTOPES (9) A STUDY WITH Fe⁵⁹ PART II

Abstract

A) Following the previous report, effects of the changes in bath conditions on the percutaneous absorption of iron in the bath water were studied further.
1) Percutaneous absorption of ferric ion proved strongest at a water temperature of 42°C, weakest at 30°C, and moderate at 37°C.
2) The more the concentration of iron in bath water rose, the more increased the percutaneous absorption of iron.
3) Iron absorbed in or adhered to the skin during the bath must infiltrate into the body after the bath as the amount of Fe⁵⁹ in the animal body, sacrificed 20min. after the bath, proved 2.5 times more than in the test animal killed immediately after the bath.
4) NaCl and AlCl₃ which were added to the bath water containing iron chloride had no marked influence on the transition of iron into the body, while KCl CaCl₂, MgCl₂, Na₂SO₄, and NaHCO₃ in the same mval% decreased more or less the infiltration of iron into the body.
B) Fur of the rabbits abdomen was shaved thoroughly and a sheet of gauze soaked with various pH solution was folded into four and adhered closely to the rabbits abdomen with cellophane tape. Then radioactive iron (ca. 60μc of Fe⁵⁹) was injected into the ear vein of rabbit. One hour after the application the gauze was taken and ignited to ashes completely in porcelain crucible at 500°C. The ash was dissolved in hydrochloric acid solution, transferred into a stainless plate, neutralized by ammoniac solution, methylred as indicator. Then precipitate was dried gradually.
Radioactivity of the precipitate was measured with Lauritsen's electroscope and following results were obtained.
1) Percutaneous elimination of radioactive iron from the body proved strongest under the condition in which the skin of the animal was wetted in acid solution, weakest in the condition of alkaline solution and moderate in the condition of neutral solution.
Addition of sodium chloride into the water, which drenched the gauze to wet the skin, promoted the percutaneous excretion of iron front the body.
2) Percutaneous elimination of iron injected intravenously became less and less as time passed.
C) Mice were bathed in natural or artificial hot spring waters once daily for two weeks at a temperature of 37°C for ten minutes to study the effect of a series of baths on the absorption of iron from the digestive tract. Radioactive iron was dissolved in 1/100 normal solution of hydrochloric acid as ferric chloride. One tenth ml of this solution contained 5 microcuries of Fe⁵⁹. It was mixed with 0.05-0.15ml of test solutions and then administered to mice with stomach tube made by Polyethylen. The mice were killed ninety minutes after the administration of the labelled iron solution. Oesophagus. stomach and all the intestine were removed in order to exclude the contamination of Fe⁵⁹ still not absorbed from the digestive tract. All the remaining body was ignited to 600°C, then dissolved in hydrochloric acid. Iron was precipitated by the same method as described above and dried gradually.
The radioactivity of the precipitate was measured with Lauritsen's electroscope and following results were obtained.
1) Iron absorption from the digestive tract was promoted by the addition of copper, and/or vitunine C in the test solution.
2) Average iron absorption from the digestive tract wits decreased by the serial thermal baths in Ikaho Hot Spring (an iron containing calcium sulphate water), in Kamimoku Hot Spring (a muriated calcium sulphate water), and in plain water, while the serial baths in sodium chloride or ferric chloride solution showed rather an increase. But these differences proved not significant.