Integrative function of adrenaline receptors for glucagon-like peptide-1 exocytosis in enteroendocrine L cell line GLUTag

Biochem Biophys Res Commun. 2015 May 15;460(4):1053-8. doi: 10.1016/j.bbrc.2015.03.151. Epub 2015 Apr 3.


Adrenaline reacts with three types of adrenergic receptors, α1, α2 and β-adrenergic receptors (ARs), inducing many physiological events including exocytosis. Although adrenaline has been shown to induce glucagon-like peptide-1 (GLP-1) secretion from intestinal L cells, the precise molecular mechanism by which adrenaline regulates GLP-1 secretion remains unknown. Here we show by live cell imaging that all types of adrenergic receptors are stimulated by adrenaline in enteroendocrine L cell line GLUTag cells and are involved in GLP-1 exocytosis. We performed RT-PCR analysis and found that α1B-, α2A-, α2B-, and β1-ARs were expressed in GLUTag cells. Application of adrenaline induced a significant increase of intracellular Ca(2+) and cAMP concentration ([Ca(2+)]i and [cAMP]i, respectively), and GLP-1 exocytosis in GLUTag cells. Blockade of α1-AR inhibited adrenaline-induced [Ca(2+)]i increase and exocytosis but not [cAMP]i increase, while blockade of β1-AR inhibited adrenaline-induced [cAMP]i increase and exocytosis but not [Ca(2+)]i increase. Furthermore, overexpression of α2A-AR suppressed the adrenaline-induced [cAMP]i increase and exocytosis. These results suggest that the fine-turning of GLP-1 secretion from enteroendocrine L cells is established by the balance between α1-, α2-, and β-ARs activation.

Keywords: Adrenaline; Adrenergic receptors; Enteroendocrine L cell; Exocytosis; Glucagon-like peptide-1.

MeSH terms

  • Animals
  • Base Sequence
  • Calcium / metabolism
  • Cell Line
  • Cyclic AMP / metabolism
  • DNA Primers
  • Enteroendocrine Cells / cytology
  • Enteroendocrine Cells / metabolism*
  • Epinephrine / metabolism*
  • Exocytosis*
  • Glucagon-Like Peptide 1 / metabolism*
  • Mice
  • Microscopy, Fluorescence
  • Polymerase Chain Reaction
  • Receptors, Adrenergic / metabolism
  • Receptors, Adrenergic / physiology*


  • DNA Primers
  • Receptors, Adrenergic
  • Glucagon-Like Peptide 1
  • Cyclic AMP
  • Calcium
  • Epinephrine