Comparison of the ability of dopamine receptor agonists to inhibit forskolin-stimulated adenosine 3'5'-cyclic monophosphate (cAMP) accumulation via D2L (long isoform) and D3 receptors expressed in Chinese hamster ovary (CHO) cells

Biochem Pharmacol. 1999 Jul 15;58(2):285-9. doi: 10.1016/s0006-2952(99)00101-x.


The pharmacological properties of the human D2L (long isoform) and rat D3 dopamine receptors in functional assays were examined. A range of dopamine agonists were assessed for their ability to inhibit adenosine 3'5'-cyclic monophosphate (cAMP) accumulation via the two receptors expressed stably in Chinese hamster ovary cells. Dopamine caused a significantly greater maximal inhibition (P < 0.05) of cAMP accumulation via the D2L receptor (approximately 70%) as compared to the D3 receptor (approximately 50%). The pattern of agonist effects was different at the two receptors. The absolute and relative potencies for inhibition of cAMP accumulation were different for a range of agonists acting at the two receptors. Similarly, the maximal inhibitions achieved by a range of agonists were different for the two receptors.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • CHO Cells
  • Colforsin / antagonists & inhibitors
  • Colforsin / pharmacology*
  • Cricetinae
  • Cyclic AMP / metabolism*
  • Dopamine / metabolism*
  • Dopamine Agonists / pharmacology*
  • Humans
  • Rats
  • Receptors, Dopamine D2 / agonists*
  • Receptors, Dopamine D2 / genetics
  • Receptors, Dopamine D2 / metabolism
  • Receptors, Dopamine D3
  • Transfection


  • DRD3 protein, human
  • Dopamine Agonists
  • Drd3 protein, rat
  • Receptors, Dopamine D2
  • Receptors, Dopamine D3
  • Colforsin
  • Cyclic AMP
  • Dopamine