In Vitro Effects of Agricultural Dusts on Guinea Pig Alveolar Macrophages.
Ma-JY; Barger-MW; May-JJ; Jones-W; Castranova-V
1993 Proceedings, Beltwide Cotton Conferences, New Orleans, Louisiana, January 10-14, 1993, National Cotton Council of America, Memphis, Tennessee 1993:255-257
The role of alveolar macrophages in pulmonary responses to agricultural dust exposure was evaluated. The effects of in-vitro exposure to alveolar macrophages to burnt hay, chopped hay, and silage were studied. In-vitro exposure of guinea-pig alveolar macrophages to silage dusts resulted in a dose dependent stimulation of oxygen consumption. Maximal stimulation of 18% was achieved at a silage concentration of 1mg/ml. Silage also stimulated the generation of chemiluminescence by guinea-pig alveolar macrophages. Dose response studies revealed two peaks, a 108% increase at 0.05mg/ml and a 91% increase at 0.5mg/ml. To determine whether the stimulatory factor in silage was a soluble agent or the particle itself, aqueous extracts of silage were tested. The aqueous extract was significantly more potent than the washed dust particles. Boiling the extract resulted in an almost complete depression of its activity. The effect of in-vitro exposure of alveolar macrophages to agricultural dust on the ability of n-formyl-methionyl-leucyl- phenylalanine (FMLP) to stimulate respiratory burst activity was also tested. Each of these dusts significantly impaired the ability of alveolar macrophages to be activated by the chemotactic peptide, FMLP. In-vitro exposure to these dusts inhibited phorbol-myristate- acetate induced stimulation of oxygen consumption by about 45%. The authors conclude that it is unlikely that direct activation of alveolar macrophages plays an important role in the pulmonary response to inhalation of these agricultural dusts.
Plant-dusts; Laboratory-animals; Organic-dusts; In-vitro-studies; Alveolar-cells; Agricultural-products; Dust-exposure; Cellular-respiration;
1993 Proceedings, Beltwide Cotton Conferences, New Orleans, Louisiana, January 10-14, 1993, National Cotton Council of America, Memphis, Tennessee