Compensatory lung growth: lung mass and protein content in trilobectomized rats

ABSTRACT

Aiming at assessing compensatory lung growth after trilobectomy in rats, 3 groups of animals (control, thoracotomy and trilobectomy) were studied over 3 time intervals (7,30 and 180 days post-operation). Body mass, lung mass and protein content in each lung were evaluated. The results reveal that, in trilobectomy animals, the remaining lung mass was restored by day 7. A fast growth rate was observed in both the left lung and cranial lobe over the 7 first days after trilobectomy. Total lung protein behaved similarly to total lung mass, demonstrating that lung mass and total protein increased proportionally. In the left lung, both mass and protein content ceased to increase by day 30, whereas in the cranial lobe this increasing still occurred by day 180. Therefore, it may be concluded that, in our experiment, compensatory lung growth after trilobectomy in adult rats occurred due to an increase in the lung protein content, suggesting a cellular volume increase (hypertrophy).