Some questions about Eurocollins solution used for lung preservation

Currently, Eurocollins' (EC) solution (high-potassium concentration) is the most widely clinically used pulmonary perfusate. However, recently, experimental studies have reported an increase of the lung ischemic period using low-potassium solutions. The purpose of our study, is to investigate the influence of the EC ionic composition and the effect of hyperosmolarity due to the glucose concentration on isolated alveolar type II epithelial cells. Pneumocytes type II were isolated from pathogen free Wistar rats using the modified Dobbs' method. Cells were incubated for 6 hours at 4 degrees C in EC, Collins (CL) and Ringer Lactate (RL) solutions. After that, cellular viability was evaluated by analysis of the protein synthesis assay by measuring the 35 S methionine uptake during an incorporation period of one hour at 37 degrees C (picomol 35 S met/mg proteins/h). Mean +/- standard deviation and Student "t"-test were used for data presentation and results comparison. Cellular viability at time 0 (control) before cellular incubation was 3.93 +/- 0.38. After 6 hours at 4 degrees C the results were respectively as follows: EC = 2.16 +/- 0.13; CL = 2.63 +/- 0; RL = 3.21 +/- 0.04. Our results suggest that the low-potassium extracellular type solution (RL) shows a protection on isolated type II epithelial cells statistically significant (p < 0.05) if compared with EC solution. Moreover CL solution, that has the same ionic composition EC but without glucose, presents a less cytotoxic effects on incubated cells than EC, confirming a deleterious influence of solution hyperosmolarity.