A comparative, histomorphological and histochemical study of lower respiratory system at different ages postnatally in male albino rats

Abstract

Histomorphological and histochemical study, by light microscopy, was undertaken on the lower respiratory system of the albino rat at two different ages (1st and 4th months). The trachea and lungs were weighted, measured and stained with Hematoxylin and eosin, Masson's Trichrome stain and PAS stain. The results revealed there's significant differences in weight of body and lung of rat pups represented by gradually increase of weight and lung respectively, at 1st and 4th month. On the other hand there were no statistical differences in trachea weights at 1st and 4th month. The diameter of trachea, bronchioles and alveolar sac significantly changes. In contrast the tracheal lumen showed no significant changes in diameter in 1st and 4th months. Thickness of mucosa, sub-mucosa and tracheal cartilage significantly changes. The most thicker of mucosa showed at 1st month while they reduced gradually at 4th. By the other hand the results of thickness measuring of interstitial tissue showed no significant changes.