SODIUM-TRANSPORT AND FLUID BALANCE IN LUNGS FROM NORMAL AND DYSTROPHIC HAMSTERS

Gravimetric and sodium transport characteristics of lungs from BIO 14. 6 (dystrophic) hamsters were compared with those of lungs from golden Syrian (normal) hamsters at 30 and 150 days of age. Isolated perfused lungs were used to determine lung permeability and fluid balance diffe rences between normal and dystrophic animals at both ages. Apparent pe rmeability-surface area products for air space-to-vascular space sodiu m, sucrose, and fluorescein isothiocyanate-labeled dextran fluxes were compared in the four groups of hamsters. Morphometric analysis of fix ed lungs of representative hamsters from each group was also performed . Dystrophic hamsters exhibited higher lung wet-to-dry weight ratios t han normal hamsters at both ages. Lungs from dystrophic hamsters were less sensitive to inhibition of sodium transport by amiloride than lun gs from age-matched normal hamsters. Dystrophic hamster lungs had high er absolute permeabilities of the passively transported solutes, lower permeability values for sodium, and only one-half of the amiloride-se nsitive sodium transport of lungs from age-matched normal hamsters. Di fferences in lung fluid balance between dystrophic and normal hamsters may be related to differences in sodium clearance.