F.O. Belzer

Combination perfusion-cold storage for optimum cadaver kidney function and utilization.

Dog kidneys were perfused with a newly developed perfusate containing adenosine and PO4 for 48 hr, stored in the same perfusate for an additional 24 hr without perfusion (total preservation time:72 hr), and transplanted with immediate contralateral nephrectomy. Posttransplant renal function and biochemical analysis of the kidneys revealed practically no additional preservation-induced damage during the cold storage period. Serum creatinine levels reached normal between the third and eighth day posttransplant. This preservation method may be the method of choice for patients receiving postoperative cyclosporine therapy--and, in addition, facilitate organ sharing between transplant centers, thus reducing wastage of cadaveric kidneys.

Effect of fasting on hepatocytes cold stored in University of Wisconsin solution for 24 hours.

Although there have been improvements in liver preservation, liver dysfunction still remains a serious consequence of liver transplantation. This may be related to cold ischemic injury since the incidence of dysfunction increases with longer preservation times. However, even some livers preserved for short periods of time (less than 15 hr) develop liver dysfunction. One possible cause may be the lack of adequate nutritional support, and the donor may be exposed to prolonged periods of hyponutrition. In this study, we have compared the effects of fasting on functions of hepatocytes isolated from the rat. Hepatocytes were cold stored in University of Wisconsin solution for 24 hr and analyzed at the end of preservation as well as at the end of rewarming in Krebs-Henseleit buffer for 120 min. The glycogen content of fed cells was 1.57 μmol/mg protein and this was reduced by 95% in cells from fasted rats. After cold storage and rewarming, hepatocytes from fasted rats lost 84.2±2.5% of the total cellular lactate dehydrogenase versus only 32.7±3.8% (P<0.001) in cells from fed rats. Also, ATP and reduced glutathione content of fasted cells were significantly reduced, free fatty acids were higher (P=0.0154), and protein synthesis was reduced to 41% of controls (versus only 88% in fed cells), although there were no differences in phospholipid content. When hepatocytes from fasted rats were rewarmed in Krebs-Henseleit buffer containing fructose (10 mM), lactate dehydrogenase release was reduced from 80% to 34.4±0.2% and ATP content was significantly higher with fructose than without. Hepatocytes from fasted rats, therefore, are more sensitive to cold ischemic injury than cells from fed rats. The increased sensitivity appears related to the lack of glycogen as a source of substrates for metabolism during rewarming. This is supported by the fact that addition of fructose, which is metabolized readily by hepatocytes through glycolysis, suppressed rewarming injury to cells from fasted rats. The nutritional status of the donor, therefore, may play a pivotal role in the results of liver preservation and transplantation. Effective donor nutritional management may reduce the incidence of liver dysfunction after transplantation.

Inhibition of Ischemic Induced Cellular Swelling in Kidney Cortex Tissue by Lactobionate Anions

Tissue slices prepared from the cortex of canine kidneys exposed to various periods of normothermic ischemia rapidly and massively swell when placed in oxygenated Ringers lactate medium. The swelling can be suppressed by replacing part of the chloride with larger, less permeable anions such as lactobionate. By adjusting the ratio of lactobionate:Cl- to 60 mM:80 mM respectively, periods of greater than 90 min of ischemia can be tolerated without cell swelling. The lactobionate:Cl- medium is effective at preventing cell swelling at osmolalities approaching isoosmolar conditions. A fluid containing the appropriate levels of lactobionate and Cl- may be beneficial in the resuscitation of ischemic or shocked exposed organ systems by suppressing reflow-related cell swelling.