Context Kidney graft function after transplantation can be improved through pharmacological donor pretreatment to limit organ injury from cold preservation. Objective To determine whether pretreatment of brain-dead donors with lowdose dopamine improves early graft function in human renal transplant recipients. Design, Setting, and Patients Randomized, open-label, multicenter, parallelgroup trial of 264 deceased heart-beating donors and 487 subsequent renal transplants performed at 60 European centers between March 2004 and August 2007 (final follow-up, December 31, 2008). Eligible donors were stable under low-dose norepinephrine with a normal serum creatinine concentration on admission. Interventions Donors were randomized to receive low-dose dopamine (4 µg/kg/min). Main Outcome Measures Dialysis requirement during first week after transplantation. Results Dopamine was infused for a median of 344 minutes (IQR, 215 minutes). Dialysis was significantly reduced in recipients of a dopamine-treated graft. Fewer recipients in the treatment group needed multiple dialyses (56/227; 24.7%; 95% CI, 19.0%-30.3%; vs 92/260; 35.4%; 95% CI, 29.5%-41.2%; P=.01). The need for multiple dialyses posttransplant was associated with allograft failure after 3 years (HR, 3.61; 95% CI, 2.39-5.45; PϽ.001), whereas a single dialysis was not (HR, 0.67; 95% CI, 0.21-2.18; P=.51). Besides donor dopamine (OR, 0.54; 95% CI, 0.35-0.83; P=.005), cold ischemic time (OR, 1.07; 95% CI, 1.02-1.11 per hour; P=.001), donor age (OR, 1.03; 95% CI, 1.01-1.05 per year; PϽ.001), and recipient body weight (OR, 1.02; 95% CI, 1.01-1.04 per kg; P=.009) were independent explanatory variables in a multiple logistic regression model. Dopamine resulted in significant but clinically meaningless increases in the donor's systolic blood pressure (3.8 mm Hg; 95% CI, 0.7-6.9 mm Hg; P=.02) and urine production before surgical recovery of the kidneys (29 mL; 95% CI, 7-51 mL; P=.009) but had no influence on outcome. Conclusion Donor pretreatment with low-dose dopamine reduces the need for dialysis after kidney transplantation.

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The present study was conducted to dissect the underlying mechanisms by which catecholamines protect cells against preservation injury.To this end, we firstly defined the cellular and molecular differences between protected and nonprotected cells and secondly defined the mediators that were involved in cold-induced damage. In conclusion we have demonstrated that catecholamines protect cells against preservation injury either by scavenging of ROS or by inhibition of ROS production.

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Background/Aims: Catecholamines prevent hypothermic cell death which accounts for severe tissue damage and impaired allograft function after prolonged organ preservation. Here, we identified cellular processes which govern hypothermia-mediated cell death in endothelial cells and how they are influenced by dopamine. Methods: Lactate dehydrogenase assay, intracellular ATP, reactive oxygen species and reduced thio-group measurement, intracellular calcium measurement and mitochondrial calcium staining were performed in the study. Results: Intracellular ATP was almost completely depleted within 12 hrs of hypothermic preservation in untreated human umbilical vein endothelial cells (HUVEC), while dopamine pre-treatment significantly delayed ATP depletion. 4 hrs after hypothermia a redox imbalance was observed in untreated cells, which increased with the duration of hypothermia. The redox imbalance was primarily caused by depletion of SH reduction equivalents and was significantly inhibited by dopamine. In addition, hypothermia-induced Ca²⁺ influx and mitochondrial Ca²⁺ accumulation were both prevented by dopamine. The protective effect of dopamine was abrogated by ionomycin and sodium azide and partly by oligomycin and CCCP. Conclusions: Our data demonstrated that loss of intracellular ATP, generation of a redox imbalance and accumulation of intracellular Ca²⁺ underlie cold preservation injury. Dopamine improves the redox balance, prevents intracellular Ca²⁺ accumulation and delays ATP depletion.

Our study demonstrates beneficial effects of dopamine treatment on cold storage induced endothelial barrier disturbances. This may contribute to the positive effects of catecholamines on immediate graft function of renal allografts in men.

SummaryAlthough a beneficial effect of hydroxy-methylglutaryl coenzyme A (HMGCoA) reductase inhibitors, i.e. statins, on cell-mediated immunity has been suggested in vivo and in vitro, little is known about the molecular and biochemical events by which statins inhibit T cell proliferation. To address this question, we investigated the effects of atorvastatin (AT) on intracellular cytokine production, T cell activation markers, cell cycle progression and apoptosis in human CD4 + T cells. AT did not influence intracellular cytokine production after short-term stimulation of whole blood with phorbol myristate acetate (PMA)/ionomycin or superantigen (SEB). In contrast, AT influenced CD45RA to RO switching dose-dependently, as well as CD25 expression, and caused cell cycle arrest in the G1 phase after long-term T cell stimulation. This occurred in conjunction with a reduced expression of cyclin-dependent kinases 2 and 4 and p21 wav1/cip1 and was paralleled by an increased protein expression of p27 kip1 . In addition to G1 arrest, increased apoptosis was observed in AT-treated cells. In line with this, the expression of Bcl-xl and pBad were decreased by AT. Apoptosis was independent of caspases 3 and 9 activation. The inhibitory effect of AT on T cell proliferation could be overcome by addition of mevalonic acid or geranylgeranyl pyrophosphate, but not by farnesyl pyrophosphate or squalen, suggesting reduced protein prenylation. Activation of Rho, Rac and Ras were strongly reduced in AT-treated T cells, suggesting that impaired geranylation of these molecules might underlie the inhibitory effect of AT on T cell proliferation.

Treatment of organ donors with catecholamines reduces acute rejection episodes and improves long-term graft survival after renal transplantation. The aim of this study was to investigate the effect of catecholamine pre-treatment on ischemia/reperfusion (I/R)- and cold preservation injury in rat kidneys. I/R-injury was induced by clamping the left kidney vessels for 60 min along with a contralateral nephrectomy. Cold preservation injury was induced by storage of the kidneys for 24 h at +4 degrees Celsius in University of Wisconsin solution, followed by syngeneic transplantation. Rats were pre-treated with either dopamine (DA), dobutamine (DB), or norepinephrine (2, 5, and 10 microg/kg/min, each group) intravenously via an osmotic minipump for 24 h before I/R- and cold preservation injury. Pre-treatment with DA (2 or 5 microg/kg/min) and DB (5 microg/kg/min) improved recovery of renal function after I/R-injury and dose dependently reduced mononuclear and major histocompatibility complex class II-positive cells infiltrating the kidney after I/R-injury. One day after I/R-injury, upregulation of transforming growth factor (TGF)-beta 1 and 2 and phosphorylation of p42/p44 mitogen-activated protein kinases was observed in kidneys of animals treated with DA or DB. DA (5 microg/kg/min) and DB (5 microg/kg/min) pre-treatment reduced endothelial cell damage after 24 h of cold preservation. Only DA pre-treatment improved renal function and reduced renal inflammation after 24 h of cold preservation and syngeneic transplantation. Our results demonstrate a protective effect of pre-treatment with catecholamines on renal inflammation and function after I/R- or cold preservation injury. This could help to explain the potent organoprotective effects of catecholamine pre-treatment observed in human kidney transplantation.