The response of the dog kidney to transplant rejection or ischaemia: an experimental and comparative study with functional, microcirculatory and enzymological investigations.

Abstract

1. The effects of transplant rejection or of total ischaemia on the dog kidney were compared by studying the following parameters: urinary clearances, microcirculation, histological aspect, blood levels of lysosomal enzymes, active transport of cortical slices, and levels of cortical ATPases. 2. At the point of rejection, allotransplanted kidneys without immunosuppressive therapy maintained almost normal active transport of glycine andβ-methylglucoside by the proximal tubular epithelium, despite greatly reduced micro-circulation and abolition of glomerular filtration. 3. 1 or 2 hours' ischaemia provoked partial tubular necrosis with an abrupt liberation of lysosomal enzymes into the circulation and a decrease in active transport. The microcirculation was less damaged. 2 days later, in spite of the partial recovery of the active transport, and discrete zones of cellular regeneration, the clearances were still non-existent. 4. The results suggest that there is little correlation between the effects of allotransplant rejection and ischaemia. The primary event in the process of rejection involves the interruption of the glomerular circulation, which leads to a rapid cessation of urine formation, without too much damage to the transport function of the tubular epithelium.