Conflicting data exist on the role of neutrophils (PMNs) in the pathogenesis of hyperoxic lung damage. We examined the contribution of PMNs and the contribution of food deprivation, a frequent complication of the methods used to produce neutropenia, to the lung damage that results when mice are exposed to high concentrations of oxygen. Mice were exposed to either 100% oxygen or air for up to 4 days. Neutropenia was induced by a single tail vein injection of nitrogen mustard (NM) given 1 day before the oxygen exposure. Food deprivation, which induced the same weight loss as that found in NM-treated mice, was achieved by withholding food (fasted) during the oxygen exposure. We examined mortality; weight loss; bronchoalveolar lavage (BAL fluid) protein concentration, cell count, and differential count; the number of PMNs in blood and lung histologic conditions by light and electron microscopy. NM-treated mice lost approximately 25% of their body weight when exposed to either air or oxygen. They also had more severe lung damage than the saline-treated mice during hyperoxic exposure, despite a marked reduction in the number of PMNs in blood, BAL fluid, and lung tissue. Although a correlation was found between the number of blood PMNs and the BAL protein concentration in the nonneutropenic mice (r = 0.69; P < 0.001), no correlation was seen in the neutropenic mice (r = 0.26). Fasted, oxygen-exposed mice had the same weight loss as the NM mice, but they had more severe lung damage at an earlier time (day 3 vs. day 4) and greater mortality than the saline-treated and the NM-treated mice. These results indicate that PMNs are not required for either the development or progression of hyperoxic lung damage in mice; fasting increases susceptibility to the lung damage; and differences in nutritional status may explain, in part, the controversial role of PMNs in oxygen-induced lung damage.
|Original language||English (US)|
|Number of pages||10|
|Journal||Journal of Laboratory and Clinical Medicine|
|State||Published - 1988|
ASJC Scopus subject areas
- Pathology and Forensic Medicine