Expression of muscarinic receptor subtypes and M2-muscarinic inhibition of adenylyl cyclase in lung

C. W. Emala, A. Aryana, M. A. Levine, R. P. Yasuda, S. A. Satkus, B. B. Wolfe, C. A. Hirshman

    Research output: Contribution to journalArticlepeer-review

    26 Scopus citations


    The relative distribution and absolute quantities of muscarinic receptor subtypes m1, m2, m3, and m4 were determined in membranes of canine trachealis muscle, bronchi, and lung parenchyma by immunoprecipitation with receptor subtype-specific rabbit polyclonal antisera. Additionally, the functional coupling of muscarinic receptors to the inhibition of adenylyl cyclase was related to the presence of m2-muscarinic receptors in each region. Immunoprecipitation identified more total muscarinic receptors in crachealis muscle than in bronchi or lung. m2-Muscarinic receptor predominated in tracheal muscle (372 ± 85 fmol/mg protein) with fewer m3 receptors (48 ± 5 fmol/mg protein). Bronchi contained 6.6 ± 2.0 and 9.2 ± 1.8 fmol/mg protein of m2 and m3 receptors, respectively. Lung parenchyma contained 13.9 ± 3.9 fmol/mg protein of m3 receptors. Adenylyl cyclase activity increased in response to guanosine triphosphate and isoproterenol in membranes from all three lung regions, but muscarinic-mediated inhibition of adenylyl cyclase occurred only in trachealis membranes. These studies provide the first quantitative assessment of muscarinic receptor subtypes in different regions of the lung and relate the ability to measure muscarinic inhibition of adenylyl cyclase to the presence of m2 receptors.

    Original languageEnglish (US)
    JournalAmerican Journal of Physiology - Lung Cellular and Molecular Physiology
    Issue number1 12-1
    StatePublished - 1995

    ASJC Scopus subject areas

    • Cell Biology
    • Physiology
    • Pulmonary and Respiratory Medicine
    • General Agricultural and Biological Sciences


    Dive into the research topics of 'Expression of muscarinic receptor subtypes and M2-muscarinic inhibition of adenylyl cyclase in lung'. Together they form a unique fingerprint.

    Cite this