Time course of pulmonary response to inhalation of cotton dust in guinea pigs and rats.
Castranova-V; Robinson-VA; Tucker-JH; Schwegler-D; Rose-DA; DeLong-DS; Frazer-DG
Cotton dust: proceedings of Eleventh Cotton Dust Research Conference, Beltwide Cotton Research Conferences, January 7-8, 1987, Dallas, Texas. Jacobs RR, Wakelyn PJ, eds. Memphis, TN: The National Cotton Council of America, 1987 Jan; :79-83
The time course of acute pulmonary response to cotton dust inhalation was assessed in guinea-pigs and rats using an improved animal exposure system. Animals were exposed to 35mg/m3 cotton dust aerosol for 2 hours; pulmonary responses were measured for 48 hours post exposure. Monitored responses included breathing rate upon CO2 challenge, number of alveolar macrophages and leukocytes lavaged from the lung, and secretory activity of alveolar macrophages. In guinea-pigs, a significant increase in breathing rate upon CO2 challenge was observed 6 hours after exposure; the response peaked at 12 to 18 hours and remained elevated at 48 hours. While leukocyte influx into the pulmonary airspaces showed a similar trend and time dependence, the number of alveolar macrophages declined immediately after exposure and returned to values slightly above control at 48 hours. Secretory activity, as assessed by zymosan induced superoxide secretion, was elevated at 12 hours, peaked at 24 hours, and was above control at 48 hours. Responses of rats differed from responses of guinea-pigs in both magnitude and time course; breathing rate was maximal immediately after dust exposure, number of leukocytes was elevated immediately after exposure, and macrophage secretory activity was unaltered until 18 hours post exposure. The authors conclude that acute pulmonary responses to cotton dust inhalation differ between the two species; responses are generally larger and more prolonged in guinea-pig than rat.
Cotton-dust; Laboratory-animals; Acute-exposure; Pulmonary-function; Dust-exposure; Dust-inhalation; Aerosols; Lung-function; Respirable-dust
Cotton dust: proceedings of Eleventh Cotton Dust Research Conference, Beltwide Cotton Research Conferences, January 7-8, 1987, Dallas, Texas