Pulmonary response of mice to aqueous cotton dust extract.
OBJECTIVE
To determine the pulmonary response of mice to acute exposure of aqueous cotton dust extract (CDE).


METHODS
CDE was made from a standard cotton mill dust. Under mild anaesthesia, 0.05 ml of CDE was instilled intratracheally in balb/c mice. The same volume of sterile isotonic saline was instilled in controls. After 1, 5 and 10, days animals were given an overdose of pentobarbital by intraperitoneal injection, and the upper thorax was opened to expose the trachea. An incision was made and cannulae was inserted. Bronchoalveolar lavage (BAL) was done by instilling, phosphate buffer saline. Total and differential counts were done. The lavage supernatant was assayed for protein.


METHODS
The laboratory of Division of Pulmonary and Critical Care Medicine, Duke University Medical Center, USA.


METHODS
Balb/c mice.


METHODS
Post-exposure acute effects at bronchoalveolar level.


RESULTS
Total and differential cell counts in BAL fluid were significantly higher in CDE exposed compared to controls (P < 0.01). The total mean values (expressed as cells x 10(4)) after exposure for days 1, 5 and 10 were 193.4 +/- 8.6, 177.8 +/- 7.7 and 113.5 +/- 6.4 respectively versus controls (41.6 +/- 3.4). Differential counts (cell no. x 10(4)) revealed 124.3 +/- 6.8, 94.2 +/- 7.9, 19.9 +/- 3.5 polymorph neutrophils (PNM) and 67.3 +/- 7.1, 81.6 +/- 9.4, 90.2 +/- 8.6 macrophages (AM) on days 1, 5 and 10 respectively compared to controls 2.8 +/- 2.3 (PMN) and 37.2 +/- 1.1 (AM). Analysis of protein (mg/ml BAL fluid) demonstrated a significant increase on exposure for days 5 and 10 (0.8 +/- 0.05 and 0.9 +/- 0.6 respectively versus controls, 0.09 + 0.01, p < 0.01).


CONCLUSIONS
Acute exposure to CDE causes influx into the air spaces of inflammatory leukocytes accompanied by an increase in lung permeability (evidenced by the presence of protein in BAL fluid). In cotton mill workers, the above factors may contribute to the development of chronic byssinosis by as yet undefined agent(s) in cotton dust.
Abebe
Y
Y
Department of Physiology, Gondar College of Medical Sciences, Ethiopia.
D000818:Animals; D001992:Bronchoalveolar Lavage Fluid / Q000737:chemistry / Q000166:cytology / Q000276:immunology; D002095:Byssinosis / Q000175:diagnosis / Q000209:etiology*; D004195:Disease Models, Animal; D018450:Disease Progression; D004391:Dust / Q000009:adverse effects*; D004781:Environmental Exposure / Q000009:adverse effects*; D003368:Gossypium / Q000009:adverse effects*; D018655:Lymphocyte Count; D008264:Macrophages; D051379:Mice; D008807:Mice, Inbred BALB C; D011506:Proteins / Q000032:analysis; D011897:Random Allocation; D013997:Time Factors
D004391:Dust; D011506:Proteins