M. Wasserman, R. Griffin
Dec 15, 1977
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Influential Citations
15
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Quality indicators
Journal
European journal of pharmacology
Abstract
Abstract Thromboxane B2 (TxB2), a major product of prostaglandin endoperoxide metabolism, was examined quantitatively for bronchoactivity in the intact, anesthetized dog and on the isolated guinea pig trachea. In the dog, TxB2 (0.1 − 30.0 μg/kg i.v.) produced dose-related decreases in airflow rate, tidal volume and dynamic lung compliance, while simultaneously increasing pulmonary airway resistance. These pulmonary changes were qualitatively similar to those observed for PGF2α, yet were only 0.07-0.11 times as effective. Aerosolized TxB2 (0.001 − 0.1%) also produced smaller alterations in pulmonary mechanics than did aerosols of PGF2α. All respiratory changes returned to pre-drug levels within 5–10 min. In the isolated tracheal preparation, TxB2 (106-104 M) contracted the strips to a lesser degree than acetylcholine, histamine, PGF2α, or two PG cyclic ether endoperoxide analogs. TxB2 appears to be a naturally occurring bronchoactive metabolite (albeit weak) in the bioconversion of arachidonic acid. Since it is produced in substantial amounts in the lungs comparable to the prostaglandins, TxB2 or its more active immediate precursor, TxB2, may be involved in regulating bronchomotor tone in the healthy state and/or bronchospasm in the pathological state.