Renal lesions in ischaemic kidneys infused with haemoglobin: an electron microscopic study

Male Wistar rats were used to study changes in ultrastructure of proximal renal tubular cells after an haemoglobin (Hb) load with or without temporary renal ischaemia. An i.v. injection of stroma-free Hb was given either 30 min before, immediately after, or 2 h after ischaemia. Appropriate control groups were used for comparison. Electron microscopic examination was performed on kidneys removed 48 h after treatment. Hb transport and degradation was markedly delayed by renal ischaemia. Hetero-ambi- and autolysosomes were found after Hb load, and the number of lysosomes was higher in animals with ischaemia than in sham-operated controls given Hb. Renal cellular damage was more pronounced in rats given Hb either 30 min before or 2 h after ischaemia than in those subjected to either Hb load or ischaemia alone. The findings show deleterious effects of haemoglobinuria in conjunction with renal ischaemia.