The effect of Gaboon viper venom on iron exchange in the rat

Plasma iron turnover (PIT) has been measured by means of 59Fe in rats treated with the haemorrhagic venom of the Gaboon viper (Bitis gabonica). Venom was administered on 3 occasions over a period of 9 days and after this time PIT had fallen from 1045 micrograms/kg/day in normal animals to 449 micrograms/kg/day in envenomated animals. Plasma iron half-life was markedly increased from 64.8 min to 417.6 min and this change was associated with a reduced uptake of 59Fe by the liver. However, marrow and spleen uptake of 59Fe was normal, as were the red-cell indices, MCH, MCV and MCHC. There was a slight reduction in total red-cell numbers and haemoglobin concentration as a result of the mild internal haemorrhage induced by the venom. It is concluded that Gaboon viper venom produces a marked disturbance of iron handling by the liver without an associated change in erythropoiesis. The mild haemorrhage was insufficient to produce a microcytic hypochromic anaemia. The results of the study provide further confirmation of the belief that standard ferrokinetic measurements give only limited information on erythropoietic status.