Hypothermia-induced loss of endothelial barrier function is restored after dopamine pretreatment: role of p42/p44 activation.
BACKGROUND
Donor dopamine usage is associated with improved immediate graft function after renal transplantation. Although prolonged cold preservation results in an increased vascular permeability, the present study was conducted to examine in vitro and in vivo if dopamine pretreatment influences endothelial barrier function under such conditions.


METHODS
To assess cold preservation injury in vitro and in vivo, cultured human umbilical vein endothelial cells (HUVEC) and Lewis donor rats were pretreated with dopamine or isotonic saline prior to cold storage. Injury was determined by lactate dehydrogenase (LDH) release, histology, and functional analysis.


RESULTS
In vitro cold storage resulted in intercellular gap formation in both untreated and dopamine pretreated HUVEC. In the latter monolayer integrity was completely restored upon rewarming and paracellular transport of fluorescein isothiocyanate-dextran was significantly reduced. In dopamine treated HUVEC, intercellular gap formation was independent of cell death and was associated with redistribution of junctional proteins and condensation of cytoskeleton proteins. In untreated HUVEC proteolysis and cell death were clearly evident after hypothermia. Closing of intercellular gaps was dependent on p42/p44 activation. Regeneration of adenosine triphosphate was only observed in dopamine pretreated cells. Only in dopamine treated Lewis renal allografts subjected to cold storage, activation of p42/p44 occurred upon rewarming. These grafts had a better renal function and displayed less inflammatory cells five days after transplantation.


CONCLUSIONS
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.
Brinkkoetter
Paul-Thomas
PT
Department of Medicine (Nephrology), University Hospital Mannheim, University of Heidelberg, Germany.
Beck
Grietje C
GC
Gottmann
Uwe
U
Loesel
Ralf
R
Schnetzke
Ulf
U
Rudic
Boris
B
Hanusch
Christine
C
Rafat
Neysan
N
Liu
Zhenzi
Z
Weiss
Christel
C
Leuvinik
Henri G D
HG
Ploeg
Rutger
R
Braun
Claude
C
Schnuelle
Peter
P
van der Woude
Fokko J
FJ
Yard
Benito A
BA
D002478:Cells, Cultured; D003080:Cold Temperature; D004298:Dopamine / Q000494:pharmacology*; D042783:Endothelial Cells / Q000502:physiology*; D004789:Enzyme Activation; D006801:Humans; D019950:Mitogen-Activated Protein Kinase 1 / Q000502:physiology*; D048052:Mitogen-Activated Protein Kinase 3 / Q000502:physiology*; D009926:Organ Preservation; D014404:Tubulin / Q000032:analysis; D014746:Vimentin / Q000032:analysis
D014404:Tubulin; D014746:Vimentin; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D004298:Dopamine