l-Stepholidine increases the frequency of sEPSC via the activation of D1 dopamine signaling pathway in rat prelimbic cortical neurons

Acta Pharmacol Sin. 2007 May;28(5):627-33. doi: 10.1111/j.1745-7254.2007.00547.x.

Abstract

Aim: To investigate the effect of l-stepholidine (SPD) on the frequency of spontaneous excitatory postsynaptic currents (sEPSC) in the pyramidal cells between layers V and VI in the prelimbic cortex (PL).

Methods: A whole-cell patch clamp in rat brain slices was used.

Results: SPD significantly increased the frequency of sEPSC in a concentration-dependent manner. A selective D1 dopamine receptor antagonist SCH23390 blocked SPD-mediated effects, whereas the D1 agonist SKF38393, but not the D2/3 antagonist sulpiride, mimicked SPD-mediated increase in the frequency of sEPSC. Moreover, both protein kinase A (PKA) inhibitor N-(2- [p-bromocinnamylamino]-ethyl)-5-isoquinolinesulfonamide hydrochloride and protein kinase C (PKC) inhibitor chelerythrine attenuated the effect of SPD on sEPSC.

Conclusion: SPD elicits its effect on the frequency of sEPSC on the PL pyramidal cells via presynaptic D1 receptors, and is dependent on PKA and PKC signaling pathways.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Berberine / analogs & derivatives*
  • Berberine / pharmacology
  • Cerebral Cortex* / cytology
  • Cerebral Cortex* / drug effects
  • Cyclic AMP-Dependent Protein Kinases / metabolism
  • Dopamine / metabolism
  • Dopamine Agonists / pharmacology*
  • Dopamine Antagonists / pharmacology*
  • Excitatory Postsynaptic Potentials / drug effects*
  • Excitatory Postsynaptic Potentials / physiology
  • Humans
  • Neurons* / cytology
  • Neurons* / drug effects
  • Neurons* / physiology
  • Patch-Clamp Techniques
  • Presynaptic Terminals / drug effects
  • Presynaptic Terminals / metabolism
  • Protein Kinase C / metabolism
  • Rats
  • Rats, Sprague-Dawley
  • Receptors, Dopamine D1 / metabolism
  • Signal Transduction / drug effects*

Substances

  • Dopamine Agonists
  • Dopamine Antagonists
  • Receptors, Dopamine D1
  • Berberine
  • stepholidine
  • Cyclic AMP-Dependent Protein Kinases
  • Protein Kinase C
  • Dopamine