Induction of muscarinic receptor subtypes in monocytic/macrophagic cells differentiated from EoL-1 cells

Abstract We demonstrated that eosinophilic leukemia cell line-1 (EoL-1 cells) differentiated into monocytic/macrophagic cells by a treatment with interferon-γ. Muscarinic receptor mRNA was not detected in untreated EoL-1 cells, and the cytosolic concentration of Ca 2+ ([Ca 2+ ] i ) did not rise either in these cells. Interestingly, when EoL-1 cells were treated with interferon-γ, mRNAs for muscarinic M 3 and M 5 receptors could be detected in these cells, along with an increase in [Ca 2+ ] i and chemotaxis induced by carbachol that could be blocked with 4-diphenylacetoxy- N -methylpiperidine methiodide (4-DAMP) and pirenzepine. These data support the functional importance of muscarinic M 3 and M 5 receptors in monocytic/macrophagic cells differentiated from EoL-1 cells. This model also provides evidence of a significant functional interaction between muscarinic M 3 and M 5 receptors.