Changes in lung morphologic features and elasticity caused by streptozotocin-induced diabetes mellitus in growing rats.

Pressure-volume characteristics and morphologic changes were investigated in lungs of growing rats with streptozotocin-induced diabetes mellitus. Lung elastic recoil examined with quasi-static, air-filled pressure-volume curves showed no significant differences from that in control rats at all lung volumes. No alterations of surfactant properties as measured by a surface balance were observed. A 24% increase in the volume proportion of alveolar wall was found in the lungs from diabetic rats. There was an increase in the relative amounts of collagen, elastin, and basal laminae in the alveolar wall. There were more alveoli per unit volume in the diabetic animals (49.12 X 10(5)) than in the control animals (39.80 X 10(5)) (p less than 0.05) and there was an increase in the surface-to-volume ratio of the lungs of the diabetic rats.