OBJECTIVE: Pulmonary endothelial function is critical in posttransplant lung performance. Hyperkalemic organ preservation solutions alter vascular endothelial function through the non-nitric oxide and non-prostacyclin pathway, but the most frequently used lung preservation solutions, Perfadex (Vitrolife Sweden, Kungsbacka, Sweden) (K(+) 6 mmol/L) and Celsior (IMTIX SangStat Company, Lyon, France) (K(+) 15 mmol/L), have not been evaluated on pulmonary endothelial protection. We compared the non-nitric oxide and non-prostacyclin-mediated endothelial function in porcine pulmonary microarteries of lung preserved by Perfadex or Celsior solution at 4 degrees C for 4 hours. METHODS: The non-nitric oxide and non-prostacyclin-mediated endothelial function was determined by measuring the membrane potential in a single pulmonary smooth muscle cell (group II, n = 6) and bradykinin-induced relaxation (group I, n = 8) in pulmonary microarteries preserved in Krebs (a, control), Perfadex (b), or Celsior (c), with inhibitors of nitric oxide and prostacyclin. RESULTS: Membrane potential hyperpolarization decreased in IIc (4.5 +/- 0.2 mV, P < .05) but was preserved (P > .05) in IIa (6.6 +/- 0.1 mV) and IIb (6.3 +/- 0.3 mV). Resting membrane potential was depolarized in IIc (-42.8 +/- 1.3 mV) compared with IIa (-58.7 +/- 0.6 mV) and IIb (-56.7 +/- 0.9 mV) (P < .05). Hyperpolarization-associated relaxation (37.3% +/- 7.2% vs 59.7% +/- 7.7%) and sensitivity (EC(50)) (-7.29 +/- 0.13 vs -7.75 +/- 0.06 log M) to bradykinin significantly (P < .05) decreased in Ic but not in Ia and Ib. CONCLUSION: This in vitro study simulating clinical conditions demonstrates that Perfadex preserves endothelium-dependent smooth muscle relaxation and hyperpolarization better than Celsior solution in regard to the electrophysiologic and mechanical properties observed at cellular and vascular levels. This study provides a new method at the level of basic science to evaluate the solutions for heart/lung preservation.
OBJECTIVE: Pulmonary endothelial function is critical in posttransplant lung performance. Hyperkalemic organ preservation solutions alter vascular endothelial function through the non-nitric oxide and non-prostacyclin pathway, but the most frequently used lung preservation solutions, Perfadex (Vitrolife Sweden, Kungsbacka, Sweden) (K(+) 6 mmol/L) and Celsior (IMTIX SangStat Company, Lyon, France) (K(+) 15 mmol/L), have not been evaluated on pulmonary endothelial protection. We compared the non-nitric oxide and non-prostacyclin-mediated endothelial function in porcine pulmonary microarteries of lung preserved by Perfadex or Celsior solution at 4 degrees C for 4 hours. METHODS: The non-nitric oxide and non-prostacyclin-mediated endothelial function was determined by measuring the membrane potential in a single pulmonary smooth muscle cell (group II, n = 6) and bradykinin-induced relaxation (group I, n = 8) in pulmonary microarteries preserved in Krebs (a, control), Perfadex (b), or Celsior (c), with inhibitors of nitric oxide and prostacyclin. RESULTS: Membrane potential hyperpolarization decreased in IIc (4.5 +/- 0.2 mV, P < .05) but was preserved (P > .05) in IIa (6.6 +/- 0.1 mV) and IIb (6.3 +/- 0.3 mV). Resting membrane potential was depolarized in IIc (-42.8 +/- 1.3 mV) compared with IIa (-58.7 +/- 0.6 mV) and IIb (-56.7 +/- 0.9 mV) (P < .05). Hyperpolarization-associated relaxation (37.3% +/- 7.2% vs 59.7% +/- 7.7%) and sensitivity (EC(50)) (-7.29 +/- 0.13 vs -7.75 +/- 0.06 log M) to bradykinin significantly (P < .05) decreased in Ic but not in Ia and Ib. CONCLUSION: This in vitro study simulating clinical conditions demonstrates that Perfadex preserves endothelium-dependent smooth muscle relaxation and hyperpolarization better than Celsior solution in regard to the electrophysiologic and mechanical properties observed at cellular and vascular levels. This study provides a new method at the level of basic science to evaluate the solutions for heart/lung preservation.