PNEUMOCYTES TYPE-II ULTRASTRUCTURAL MODIFICATIONS AFTER STORAGE IN PRESERVATION SOLUTIONS FOR TRANSPLANTATION

Although lung transplantation represents a real therapeutic opportunit y, the problem of preserving the organ for a prolonged period (> 10 h) still remains unsolved. Further studies are necessary to fully unders tand the behavior of different lung cell types during the ischemic per iod. As ultrastructural modifications of cells of lung samples stored in different means of preservation represent an index of the integrity and therefore of cellular viability, in the present work we have comp ared the time-related ultrastructural changes in human pneumocytes typ e II cells after hypothermic (10 degrees C) storage for 6 and 12 h in University of Wisconsin (UW) solution and in low potassium dextran (LP D) solution. An ultrastructural grading scale was used to quantify the damage and the results confirmed what was observed microscopically. S tatistical analysis (t test) of the data showed that after 6 h in LPD solution, pneumocytes type II were less damaged than those stored in U W solution; these differences were statistically significant (p < 0.05 ). In our opinion, ultrastructural studies should be considered among the methods presently used to assess the effectiveness of different st orage fluids.