Ventilation, lung volumes and lung mechanics of young adult and old Syrian hamsters.

The breathing pattern, subdivisions of lung volume and quasistatic pressure-volume relationships of 15 and 65 week old hamsters (Mesocricetus auratus) anesthetized with halothane were measured by plethysmography. Body weights, tidal volumes and minute volumes of the younger and older groups were nearly identical. All lung volumes were larger in the older hamsters but there were no significant age-related differences in the relative proportions of lung volume subdivisions. Quasistatic lung compliance was greater in the older group but differences in pressure-volume relationships were not significant when volume was expressed as percent of total lung capacity. It appears that hamster lungs undergo significant volume changes with age during adulthood, but the pattern of change is different from that observed in man and dogs.