Low potassium dextran lung preservation solution reduces reactive oxygen species production.
BACKGROUND
Low potassium dextran lung preservation solution has reduced primary graft failure in animal and human studies. Though the mechanism of reducing primary graft failure is unknown, low potassium dextran differs most significantly from solutions such as Euro-Collins (EC) and University of Wisconsin in its potassium concentration. The aim of this study was to investigate the impact that potassium concentration in lung preservation solutions had on pulmonary arterial smooth muscle cell depolarization and production of reactive oxygen species.


METHODS
Using isolated pulmonary artery smooth muscle cells from Sprague-Dawley rats, the patch-clamp technique was used to measure resting cellular membrane potential and whole cell potassium current. Measurements were recorded at base line and after exposure to low potassium dextran, EC, and University of Wisconsin solutions. Pulmonary arteries from rats were isolated from the main pulmonary artery to the fourth segmental branch. Arteries were placed into vials containing low potassium dextran, EC, low potassium EC, Celsior, and University of Wisconsin solutions with reactive oxygen species measured by lucigenin-enhanced chemiluminescence.


RESULTS
Pulmonary artery smooth muscle cell membrane potentials had a significant depolarization when placed in the University of Wisconsin or EC solutions, with changes probably related to inhibition of voltage-gated potassium channels. Low potassium dextran solution did not alter the membrane potential. Production of reactive oxygen species as measured by chemiluminescence was significantly higher when pulmonary arteries were exposed to University of Wisconsin or EC solutions (51,289 +/- 5,615 and 35,702 +/- 4353 counts/0.1 minute, respectively) compared with low potassium dextran, Celsior, and low potassium EC (12,537 +/- 3623, 13,717 +/- 3,844 and 15,187 +/- 3,792 counts/0.1 minute, respectively).


CONCLUSIONS
Preservation solutions with high potassium concentration are clearly able to depolarize the pulmonary artery smooth muscle cells and increase pulmonary artery reactive oxygen species production. Low potassium preservations solutions may limit reactive oxygen species production and thus reduce the incidence of primary graft failure in lung transplantation.
Kelly
Rosemary F
RF
Department of Surgery, Veterans Affairs Medical Center, Minneapolis, Minnesota 55417, USA. kelly071@umn.edu
Murar
Jozef
J
Hong
Zhigang
Z
Nelson
Daniel P
DP
Hong
Fangxiao
F
Varghese
Anthony
A
Weir
E Kenneth
EK
D000241:Adenosine / Q000494:pharmacology; D000493:Allopurinol / Q000494:pharmacology; D000818:Animals; D003911:Dextrans / Q000494:pharmacology*; D004187:Disaccharides / Q000494:pharmacology; D004573:Electrolytes / Q000494:pharmacology; D005947:Glucose / Q000494:pharmacology*; D005971:Glutamates / Q000494:pharmacology; D005978:Glutathione / Q000494:pharmacology; D006085:Graft Survival / Q000187:drug effects*; D006639:Histidine / Q000494:pharmacology; D006982:Hypertonic Solutions / Q000494:pharmacology; D066298:In Vitro Techniques; D007328:Insulin / Q000494:pharmacology; D008163:Luminescent Measurements; D016040:Lung Transplantation / Q000473:pathology*; D008353:Mannitol / Q000494:pharmacology; D008564:Membrane Potentials / Q000187:drug effects; D009131:Muscle, Smooth, Vascular / Q000187:drug effects* / Q000473:pathology; D009926:Organ Preservation / Q000379:methods*; D019188:Organ Preservation Solutions / Q000494:pharmacology*; D011188:Potassium; D015221:Potassium Channels / Q000187:drug effects; D011887:Raffinose / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D017382:Reactive Oxygen Species / Q000378:metabolism*
C088453:Celsior; D003911:Dextrans; D004187:Disaccharides; D004573:Electrolytes; C037096:Euro-Collins' solution; D005971:Glutamates; D006982:Hypertonic Solutions; D007328:Insulin; D019188:Organ Preservation Solutions; D015221:Potassium Channels; D017382:Reactive Oxygen Species; C055206:University of Wisconsin-lactobionate solution; C083290:low potassium dextran glucose solution; D008353:Mannitol; D006639:Histidine; D000493:Allopurinol; D005978:Glutathione; D005947:Glucose; D000241:Adenosine; D011887:Raffinose; D011188:Potassium