[Changes of surfactant A and B in alveolar type II cells in hamster with elastase-induced emphysema].

OBJECTIVE

To observe the changes of surfactant A and B (SP-A and SP-B) in alveolar type II cells of lungs in hamsters with elastase-induced emphysema.

METHODS

After intratracheal instilling of elastase, hamsters were killed at the 30th, 60th and 90th day of the experiment respectively. Slides of lung tissue were examined under light microscope and measured by calculating the mean linear intercepts. Then the slides were stained under immunohistochemistry procedures and measured by using a morphometric analysis system. Meanwhile, slides were also checked by electron microscopy.

RESULTS

In comparison with the normal group, MLI of the elastase group was significantly increased (P < 0.01). Immunohistochemistry showed that the percentage of both SP-A and SP-B positive cells was significantly decreased 30 days after the intratracheal instilling of elastase (from 48.0% +/- 3.0% to 9.5% +/- 4.0% and from 28.0% +/- 4.0% to 13.3% +/- 4.1%, respectively; P < 0.01), however, a time-dependent recovery 90 days after instilling was seen. Electron microscopy showed a significantly decrease of the number of lamellae.

CONCLUSION

The decrease of SP-A and SP-B in alveolar type II cells seems to play an important role in the development of emphysema.