Effect of Inhaled Endotoxin on Pulmonary Vascular Tone and Alveolar Macrophages in Guinea Pigs.
Russell-JA; Robinson-VA; Huffman-L; Judy-D; Whitmer-M; Castranova-V
1994 Proceedings, Beltwide Cotton Conferences, San Diego, California, January 5-8, 1994, National Cotton Council of America, Memphis, Tennessee 1994 Jan; 1:318-321
The effects of inhaled endotoxin on pulmonary vascular tone and alveolar macrophages were investigated in English-short-hair-guinea- pigs. Guinea-pigs were exposed to lyophilized Enterobacter- agglomerans endotoxin that was administered via nebulizer into an inhalation chamber for 3 hours (hr). Controls were exposed to filtered air. Guinea-pigs were sacrificed at 5 to 20hr postexposure, and pulmonary arteries were tested for contractility to phenylephrine (PE). Results showed that the breathing rates of exposed guinea-pigs increased by 40% immediately after exposure. PE contractility assays showed that there were no significant differences between exposed guinea-pigs and controls. Inhaled endotoxin had no effect on the generation of endogenous nitric- oxide, in both endothelium intact and endothelium denuded guinea- pigs. Lung lavage showed that total number of cells recovered increased significantly in guinea-pigs exposed to endotoxin inhalation, and that all of the increase was in leukocytes and red blood cells, whereas alveolar macrophages did not increase in number. Zymosan stimulated chemiluminescence (ZSCL) levels were significantly higher in alveolar phagocytes from guinea-pigs exposed to endotoxin. Incubation of alveolar macrophages with an inhibitor of nitric-oxide-synthase did not significantly reduce ZSCL levels. The authors conclude that nitric-oxide does not appear to enhance the production of reactive species by alveolar macrophages of guinea- pigs exposed to inhaled endotoxin.
Bacterial-dusts; Bronchial-asthma; Inhalation-studies; Laboratory-animals; Lung-disorders; Respiratory-hypersensitivity; Endotoxins;
1994 Proceedings, Beltwide Cotton Conferences, San Diego, California, January 5-8, 1994, National Cotton Council of America, Memphis, Tennessee