Pulmonary responses of guinea pigs to consecutive exposures to cotton dust.
Castranova-V; Jones-TA; Barger-MW; Afshari-A; Frazer-DG
Cotton dust: proceedings of the Fourteenth Cotton Dust Research Conference, beltwide cotton research conferences, January 12-13, 1990, Las Vegas, Nevada. Jacobs RR, Wakelyn PJ, Domelsmith LN, eds. Memphis, TN: The National Cotton Council of America, 1990 Jan; :131-135
Pulmonary responses to repeat exposures to cotton dust were studied in guinea-pigs. English-short-hair-guinea-pigs were exposed to 25mg/m3 cotton dust 6 hours daily for 5 days and again on day eight (Monday). Breathing frequency in response to carbon-dioxide challenge was measured 17 hours after each exposure. The lungs were lavaged at these times. Lavage fluid total and differential cellularity was determined. The alveolar macrophages were recovered. Superoxide release by resting and zymosan stimulated alveolar macrophages was measured. A single cotton dust exposure increased breathing frequency by 70%. The increase fell to 39% by day five and to 22% after the weekend. Dust exposure on day eight caused breathing frequency to increase to 25% above the control value. A similar pattern, large increases after the first exposure followed by decreases on days two through five and an increase after exposure on day eight, was seen in lavage fluid total cellularity, lymphocyte and granulocyte counts, and alveolar macrophage secretion of superoxide. Changes in the number of alveolar macrophages in the lavage fluid did not show this pattern. The number of macrophages was decreased slightly after the first exposure, but increased progressively over the next 4 days, reaching a peak value of 154% over the control value by day five. The macrophage counts decreased over the weekend and after the exposure on day eight. The authors conclude that breathing rate, leukocyte influx, and particle stimulated superoxide release by alveolar macrophages show a Monday accentuation in guinea-pigs exposed to cotton dust.
Cotton-dust; Pulmonary-function; In-vivo-studies; Laboratory-animals; Inhalation-studies; Lung-cells; Alveolar-cells; Physiological-response;
Jacobs-RR; Wakelyn-PJ; Domelsmith-LN
Cotton dust: proceedings of the Fourteenth Cotton Dust Research Conference, beltwide cotton research conferences, January 12-13, 1990, Las Vegas, Nevada