Leukotriene metabolism and action in amphibians: A model system

✍ Scribed by Herman, Ceil A. ;Heller, R. Scott ;Herman, R. Peter

• Publisher: John Wiley and Sons
• Year: 1990
• Tongue: English
• Weight: 307 KB
• Volume: 256
• Category: Article
• ISSN: 0022-104X
• DOI: 10.1002/jez.1402560428

✦ Synopsis

Sulfidopeptide leukotrienes (LTs) include LTC,, LTD,, and LTE,. They contract airway smooth muscle and reduce heart contractility in mammals. In this study, LTC,, LTD,, and LTE, were compared for their effects on bullfrog heart and lung contractility in vitro. LTC,, LTD4, and LTE, all stimulated lung contraction and increased heart contractility, but LTC, was more potent than the other two leukotrienes. LY 171883, a mammalian LTD, receptor antagonist, failed to block the heart and lung responses to LTC, but did blunt the responses to LTD, and LTE,. Metabolism studies carried out with 3H-LTC4 demonstrated conversion to LTD4 and small amounts of LTE, by heart, but not by lung. Thus, bullfrogs respond to leukotrienes in ways which may be similar to (increase in lung contractility) or different from (increase in heart contractility) mammals. Leukotriene receptors appear to be highly conserved, despite the fact that tissue responsiveness to leukotrienes has changed over evolutionary time.