A recombinant calcitonin receptor independently stimulates 3',5'-cyclic adenosine monophosphate and Ca2+/inositol phosphate signaling pathways

Mol Endocrinol. 1992 Apr;6(4):551-6. doi: 10.1210/mend.6.4.1316547.


Calcitonin (CT), a polypeptide hormone, regulates calcium homeostasis by activating surface receptors coupled to stimulation of adenylyl cyclase in bone and kidney cells. CT has also been reported to increase cytoplasmic Ca2+ in osteoclasts and renal tubule cells. Signaling pathways activated by a recombinant porcine renal calcitonin receptor transiently expressed in HEK-293 cells were studied. In cells expressing the recombinant CT receptor, salmon CT stimulated cAMP accumulation (EC50, 0.16 nM) and synthesis of inositol phosphates (IP; EC50, 3.7 nM). Two other recombinant receptors, the m1-muscarinic acetylcholine receptor and the LH receptor, activated synthesis of either IP or cAMP, respectively, but not both. Stable expression of the CT receptor in a CT receptor-deficient cell line, M18, restored the cells' ability to increase cytoplasmic Ca2+ in response to salmon CT. These results show that a single recombinant CT receptor can independently activate effector pathways mediated by cAMP and IP/Ca2+.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Calcitonin / metabolism
  • Calcitonin / pharmacology*
  • Calcium / metabolism*
  • Cell Line
  • Cyclic AMP / metabolism*
  • Humans
  • Inositol Phosphates / metabolism*
  • Kinetics
  • Plasmids
  • Receptors, Calcitonin
  • Receptors, Cell Surface / drug effects
  • Receptors, Cell Surface / genetics
  • Receptors, Cell Surface / physiology*
  • Recombinant Proteins / drug effects
  • Recombinant Proteins / metabolism
  • Signal Transduction*
  • Transfection


  • Inositol Phosphates
  • Receptors, Calcitonin
  • Receptors, Cell Surface
  • Recombinant Proteins
  • Calcitonin
  • Cyclic AMP
  • Calcium