A study was made of the acute and chronic (15 days) functional and morphologic effects on the rat kidney of warm ischemia and contralateral nephrectomy, in order to define a suitable animal model for testing renal transplant preservation techniques when warm ischemia is a contributing factor. Spontaneous recovery from 30-min warm ischemia was complete, and the model was consequently unsuitable; the high mortality from 90 min was unacceptable. Warm ischemia of 60 minutes produced severe renal tubular necrosis, an acceptable mortality, residual morphologic damage, and impairment of isolated kidney perfusion parameters at 15 days. Renal function in vivo was normal in many of these animals, despite appreciable residual morphologic changes, and it is evident that functional data alone are not sufficient for assessment of preservation regimens.
