Dopamine induces intracellular Ca2+ signals mediated by alpha1B-adrenoceptors in rat pineal cells

Eur J Pharmacol. 2001 Oct 26;430(1):9-17. doi: 10.1016/s0014-2999(01)01250-x.


We have studied the functional interaction of dopamine with alpha1-adrenoceptor subtypes by measuring intracellular Ca2+ levels in pineal cells, a cell type where adrenoceptors are well characterized. We show that dopamine induces transient intracellular Ca2+ signals in only 70% of cells responding to phenylephrine. Dopamine-induced Ca2+ signals desensitise faster than Ca2+ transients elicited with phenylephrine and are selectively blocked by desipramine, imipramine, and alpha1B-adrenoceptor antagonists. These results suggest that dopamine induced Ca2+ signals are mainly due to the activation of one subtype of alpha-adrenoceptor, the alpha1B.

Publication types

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

MeSH terms

  • Adrenergic alpha-1 Receptor Antagonists
  • Adrenergic alpha-Antagonists / pharmacology
  • Animals
  • Calcium / metabolism*
  • Dopamine / pharmacology*
  • Dopamine Agonists / pharmacology
  • Male
  • Phenylephrine / pharmacology
  • Pineal Gland / drug effects*
  • Pineal Gland / metabolism
  • Prazosin / pharmacology
  • Rats
  • Rats, Wistar
  • Receptors, Adrenergic, alpha-1 / drug effects*
  • Receptors, Catecholamine / antagonists & inhibitors
  • Signal Transduction


  • Adra1b protein, rat
  • Adrenergic alpha-1 Receptor Antagonists
  • Adrenergic alpha-Antagonists
  • Dopamine Agonists
  • Receptors, Adrenergic, alpha-1
  • Receptors, Catecholamine
  • Phenylephrine
  • Calcium
  • Dopamine
  • Prazosin