Final Report. Pharmacological Studies Of Bronchoconstriction.
Pharmacological aspects of bronchoconstriction were studied in-vitro and experimental results were summarized. Experiments using smooth muscles from dogs indicated that the sodium/potassium pump of the cells contributed to the negativity of the resting membrane potential. The rabbit aorta was used as a model for developing calcium transport adenosine-triphosphatase (ATPase) assays. Reserpine (50555) altered the calcium transport properties of extramitochondrial organelles in subcellular rabbit homogenates. Microsomes from dog smooth muscles were incubated with calmodulin (77107461) which stimulated the calcium transport ATPase of the microsomes. Calmodulin also mediated the inhibitory effect of calcium on sodium/potassium ATPase activity in the microsomes. Rats were treated intratracheally with aerosols containing volcanic ash, and the effects of 5-hydroxytryptamine (50679), acetylcholine (51843), potassium, and isoproterenol (7683592) were assessed. Volcanic ash eliminated the response of rat smooth muscle to 5- hydroxytryptamine, but not to acetylcholine or potassium. The relaxation effect of isoproterenol was not affected by the ash.
NIOSH-Author; Cytochemistry; Animal-studies; Lung-function; Biomechanics; Analytical-models; Neurophysiological-effects; Medical-research; Biological-effects; In-vivo-studies;
50-55-5; 77107-46-1; 50-67-9; 51-84-3; 7683-59-2;
NTIS Accession No.
NIOSH, U.S. Department of Health, Education, and Welfare, 5 pages,