Effect of Irradiation on the Excretion of Radiosodium from the Gills of Goldfish, Carassius auratus L.

Abstract

Irradiated fish excrete (renal plus gill) much more sodium than the controls. When the fish are injected with radiosodium 1 day after irradiation, the rate of radiosodium excretion through the gills is more than double that of the controls. This rate gradually drops until the fish die. When the head is exposed and the body is shielded against irradiation, the rate of radiosodium excretion is similar to that of the whole-body-irradiated fish; but if the head is shielded and the body is exposed to the irradiation, the fish behave like the controls. It is concluded that the loss of sodium may lead to a significant lowering of osmotic pressure of the body fluids and hence may be one of the major causes of death after irradiation in fish.