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Functional effects of dimethylsulfoxide (DMSO) in the perfused kidney
ABSTRACTS-ELEVENTH
,4NNUAL
principal disadvantages of difficulty to direct the microwave energy where it is needed, and the fast that microwaves are quite lethal. The problem of electrically thawing an organ rapidly and uniformly is made difficult by the strong dependence of the electrical properties with temperature, leading to thermal runaway. Measurements indicate an increase of lo3 in electrical conductivity and of 25 in dielectric constant from the frozen to the thawed state. Analytical and experimental studies of the microwave heating of frozen spheres and kidneys indicate that either inside-out or outside-in thawing is possible, but that rapid uniform thawing still requires a degree of sophistication not yet achieved. Nevertheless, recent experiments with frozen rat skin indicate that survival rates of 70% can be achieved using microwaves of either 2450 or 915 mHz, and are somewhat superior to survival rates of skin thawed by thermal conduction. Results with reimplanted canine kidneys thawed at the above frequencies indicate that one month survival with at best minimal function is quite common.
96.
Effect of Thnu;ing Canine Kidneys
Methods
On Surcir;al
of
-75°C. SUNA~ KUBOTA, E. F. GRAHAM, B. G. CHABO, AND RICHARD C. LILLEHEI (Department of Surgery, University of Minnesota Hospitals and Department of Animal SC:ences, University of Minnesota, Mayo Memorial Building Box 21, Minneapolis, hlinnesota 55455). after
Storage
at
Canine kidneys were frozen to -75°C and stored for up to 10 days. Prior to cooling the kidneys were perfused with 800 ml cryoprecipitated plasma containing lZ.I;% DMSO, 10 mg/g kidney wt methylprednisolone, 1.0 mg isoproterenol, 2.0 mg fluorophenylalanine, 1.0 g Mg So, and 1000 U. heparin. The kidneys were cooled at 2.5-3.5” C/min from 5 to -75°C. Thawing was accomplished with microwaves using 2450 MHz frequency (Croup 1) and a combination of 2450 and 915 MHz frequencies (Group 2). After thawing, the kidneys were perfused with 350 ml cryoprecipitated plasma containing 2.5% DMSO, 1.0 g fluorophenylalaninc, 8 meqniv. KCL, and 1000 U. heparin. All 10 kidneys in Group 1 failed to function normally and underwent autolysis in 3-5 days. Renal cell damage after thawing was severe and assayed by enzymes in the venous effluent: LDH, 8.6 * 0.7 (SE) units/ml/g; GOT, 11.6 2 1.2 unit/ml/g in the first 20 ml of effluent perfusate. The temperature gradient between the cortrx and the medulla was 35°C after 50-set thawing. In
MEETING
contrast, two of 12 kidneys in Group 2 did not autolysis and secreted urine for one month as autografts. Contralatera nephrectomy was then done and the dogs lived for 5 days afterwards. By enzyme analysis renal cell damage was loss in this group: LOH, 67 k 1.2 (p = O.l), GOT, 2.2 F 0.3 (SE ) unit/ml/g, P = 0.005 and appears to be a result of uniform thawing with no temperature differential between the cortex and the medulla. These were the first kidneys to show any function after freezing to -75°C and indicate that a more lmiform thawing technique gives promise of long-term success with kidneys frozen to this temperature which would allow prolonged storage of organs for the first time.
97. Ftmctionul (DMSO)
Effects Dirnetl~yl.uulfoxitle of in the Perfused Kidney. A. 1-I. ht. C. FONTELES,* AND A. M.
JESKE, KAROW, 1~. ( Departments of Pharmacology and Surgery, Medical College of Georgia, Augusta, Georgia 30902).
While the role of DMSO as a cryoprotectant in whole organs has been established, cryoprotective concentrations of this agent may contribute to loss of functional integrity of kidneys subjected to freeze-thaw preservation regimens. In order to investigate functional alterations produced by DMSO in the absence of freezing and thawing, isolated rabbit kidneys were perfused at 37°C with various concentrations of DMSO (0.0, 1.4, and 2.8 AT) in a K+-Mg’+-rich solution. Following an initial IO-min period of perfusion without DMSO, kidneys were perfused with the varions DMSO concentrations for an additional 50 min. Vascular resistance, creatinine clearance, and fractional Ns’ reabsorption were determined at lo-min intervals, and these functional parameters were altered to varying degrees by DMSO perfusion. Kidney weight gain did not exceed control values after perfusion with 1.4 XI DMSO, but was significantly increased after perfusion with 2.8 hi DMSO. Correlative ultrastructural studies of the effects of DMSO on renal tissue indicate that functional alterations may he related to structural changes. These studies suggest that DMSO can alter renal integrity in the absence of freezing and thawing. (Supported by NIH Grant (ZM-08472-13).
98. The Influence of Chlorpromazine Yretreutmerit and 24 Hours Cold Preservation in Collins Solution on the Tubuiar Function of Kidneys Exposed to Warm Ischaemia. J. I. DAHLAGEH" AND T. BILDE* pitalct, 2100 Copenhagen fl, Iutroduced by H. Lekkegaard.
(R&ho+ I>cnm;trk
).
,4NNUAL
principal disadvantages of difficulty to direct the microwave energy where it is needed, and the fast that microwaves are quite lethal. The problem of electrically thawing an organ rapidly and uniformly is made difficult by the strong dependence of the electrical properties with temperature, leading to thermal runaway. Measurements indicate an increase of lo3 in electrical conductivity and of 25 in dielectric constant from the frozen to the thawed state. Analytical and experimental studies of the microwave heating of frozen spheres and kidneys indicate that either inside-out or outside-in thawing is possible, but that rapid uniform thawing still requires a degree of sophistication not yet achieved. Nevertheless, recent experiments with frozen rat skin indicate that survival rates of 70% can be achieved using microwaves of either 2450 or 915 mHz, and are somewhat superior to survival rates of skin thawed by thermal conduction. Results with reimplanted canine kidneys thawed at the above frequencies indicate that one month survival with at best minimal function is quite common.
96.
Effect of Thnu;ing Canine Kidneys
Methods
On Surcir;al
of
-75°C. SUNA~ KUBOTA, E. F. GRAHAM, B. G. CHABO, AND RICHARD C. LILLEHEI (Department of Surgery, University of Minnesota Hospitals and Department of Animal SC:ences, University of Minnesota, Mayo Memorial Building Box 21, Minneapolis, hlinnesota 55455). after
Storage
at
Canine kidneys were frozen to -75°C and stored for up to 10 days. Prior to cooling the kidneys were perfused with 800 ml cryoprecipitated plasma containing lZ.I;% DMSO, 10 mg/g kidney wt methylprednisolone, 1.0 mg isoproterenol, 2.0 mg fluorophenylalanine, 1.0 g Mg So, and 1000 U. heparin. The kidneys were cooled at 2.5-3.5” C/min from 5 to -75°C. Thawing was accomplished with microwaves using 2450 MHz frequency (Croup 1) and a combination of 2450 and 915 MHz frequencies (Group 2). After thawing, the kidneys were perfused with 350 ml cryoprecipitated plasma containing 2.5% DMSO, 1.0 g fluorophenylalaninc, 8 meqniv. KCL, and 1000 U. heparin. All 10 kidneys in Group 1 failed to function normally and underwent autolysis in 3-5 days. Renal cell damage after thawing was severe and assayed by enzymes in the venous effluent: LDH, 8.6 * 0.7 (SE) units/ml/g; GOT, 11.6 2 1.2 unit/ml/g in the first 20 ml of effluent perfusate. The temperature gradient between the cortrx and the medulla was 35°C after 50-set thawing. In
MEETING
contrast, two of 12 kidneys in Group 2 did not autolysis and secreted urine for one month as autografts. Contralatera nephrectomy was then done and the dogs lived for 5 days afterwards. By enzyme analysis renal cell damage was loss in this group: LOH, 67 k 1.2 (p = O.l), GOT, 2.2 F 0.3 (SE ) unit/ml/g, P = 0.005 and appears to be a result of uniform thawing with no temperature differential between the cortex and the medulla. These were the first kidneys to show any function after freezing to -75°C and indicate that a more lmiform thawing technique gives promise of long-term success with kidneys frozen to this temperature which would allow prolonged storage of organs for the first time.
97. Ftmctionul (DMSO)
Effects Dirnetl~yl.uulfoxitle of in the Perfused Kidney. A. 1-I. ht. C. FONTELES,* AND A. M.
JESKE, KAROW, 1~. ( Departments of Pharmacology and Surgery, Medical College of Georgia, Augusta, Georgia 30902).
While the role of DMSO as a cryoprotectant in whole organs has been established, cryoprotective concentrations of this agent may contribute to loss of functional integrity of kidneys subjected to freeze-thaw preservation regimens. In order to investigate functional alterations produced by DMSO in the absence of freezing and thawing, isolated rabbit kidneys were perfused at 37°C with various concentrations of DMSO (0.0, 1.4, and 2.8 AT) in a K+-Mg’+-rich solution. Following an initial IO-min period of perfusion without DMSO, kidneys were perfused with the varions DMSO concentrations for an additional 50 min. Vascular resistance, creatinine clearance, and fractional Ns’ reabsorption were determined at lo-min intervals, and these functional parameters were altered to varying degrees by DMSO perfusion. Kidney weight gain did not exceed control values after perfusion with 1.4 XI DMSO, but was significantly increased after perfusion with 2.8 hi DMSO. Correlative ultrastructural studies of the effects of DMSO on renal tissue indicate that functional alterations may he related to structural changes. These studies suggest that DMSO can alter renal integrity in the absence of freezing and thawing. (Supported by NIH Grant (ZM-08472-13).
98. The Influence of Chlorpromazine Yretreutmerit and 24 Hours Cold Preservation in Collins Solution on the Tubuiar Function of Kidneys Exposed to Warm Ischaemia. J. I. DAHLAGEH" AND T. BILDE* pitalct, 2100 Copenhagen fl, Iutroduced by H. Lekkegaard.
(R&ho+ I>cnm;trk
).