Effect of amiloride in human and sheep parietal pleura

The fluid and solute transport properties of human parietal pleura were studied and compared with sheep parietal pleura in vitro. The pleura was mounted as a planar sheet between Ussing-type chambers. The results presented are the mean values of nine different experiments. The transepithelial electrical resistance (R(TE)) of both pleurae species was measured before and after the addition of amiloride in both sides of pleura. The R(TE) for human was 25.74 +/- 1.23 Ohm.cm(2), while for the sheep it was 38.18 +/- 0.83 Ohm.cm(2). The addition of amiloride to the serosal bathing solution increased the R(TE) of human pleura to 30.48 +/- 1.01 Ohm.cm(2) and sheep pleura to 40.32 +/- 0.82 Ohm.cm(2), while amiloride had no effect on the basolateral side. From the above, it is strongly suggested that the human pleura seems to be more leaky than sheep pleura. Although the R(TE) was increased in both pleurae, the elevation in human pleura was significantly higher, thus results from experiments in sheep pleura could only partly be extrapolated in human pleura. (C) 2002 Elsevier Science B.V. All rights reserved