Hypoxanthine excretion during preservation of rabbit kidneys for transplantation. An assessment of the ischaemic damage.

The loss of 5'-adenine nucleotides from kidney tissue subjected to acute ischaemia can be indirectly estimated by washing out the end product of catabolism, hypoxanthine, from the ischaemic tissue to the perfusate. As a correlation has previously been demonstrated between the duration of the previous normothermic ischaemia and the washout of hypoxanthine during preservation, hypoxanthine has been studied as a prospective measurement of ischaemic renal damage, by transplantation of rabbit kidneys. The results were compared to the already established parameters L-lactate and lactate dehydrogenase. Different ischaemic traumata and methods of preservation have been employed in order to determine the relationship of these parameters to the ischaemic kidney damage as evaluated by the functional regeneration of the grafts after autotransplantation. The wash-out of hypoxanthine was found to be correlated to such a degree to the reversibility of the ischaemic cell degeneration that a certain in vitro exclusion of the irreversibly damaged kidney grafts was possible. It is concluded that hypoxanthine can function as a reliable and sensitive measurement for the in vitro establishment of the ischaemic kidney parenchymal damage, and that it can be employed clinically with advantage.