METABOLISM AND PATHOPHYSIOLOGY OF SODIUM AND CHLORINE IN TISSUE AFTERNEUTRON-IRRADIATION

The photon emission of tissue was measured after radiotherapy with var ious doses of fission neutrons. Spectral analyses of the decay rates r esulted in data for the exchange of sodium and chlorine between the ir radiated tissue and the whole body. In 12 cases we found that about th ree fifths of Na and Cl exchange rapidly between the extravascular and vascular liquids with a turnover half-life of 13 +/- 2 min. Slowly ex changeable or non-exchangeable fractions are deposited in the soft tis sue. New defined mass exchange rates for Na and Cl amount to an averag e of 0.8 mval min-1 kg-1 of soft tissue. The turnover of the electroly tes in tissue with large tumours is about twice that in tissues with s mall metastasis. Depending on dose, radiotherapy led in all cases to d istinct variations of the metabolism. A maximum of the exchange of Cl combined with a minimum of Na occurs at about 85 Gy of conventional or at 10 Gy of lead-filtered fission neutron radiation. These results sh ow directly for the first time the local response of the electrolyte m etabolism to therapy.