Mu and delta opioids but not kappa opioid inhibit voltage-activated Ba2+ currents in neuronal F-11 cell

Brain Res. 1997 Aug 22;766(1-2):66-71. doi: 10.1016/s0006-8993(97)00537-4.

Abstract

Whole-cell patch-clamp recordings were used to study Ba2+ currents through voltage-dependent Ca2+ channels in dorsal root ganglion x mouse neuroblastoma hybrid (F-11) cells. Opioid agonists selective for either mu (Tyr-D-Ala-Gly-Mephe-Gly-ol; DAMGO) or delta (Tyr-D-Pen-Gly-Phe-D-Pen-OH; DPDPE) receptors inhibited high-threshold Ba2+ currents. The inhibition was reversible, naloxone-sensitive, and dose-dependent. The inhibitory effects of both DAMGO and DPDPE were blocked by pretreatment of the cells with pertussis toxin (PTX) as well as by brief exposure to the sulfhydryl alkylating agent, N-ethylmaleimide (NEM). The N-type Ca2+ channel antagonist omega-conotoxin GVIA (omega-CTX GVIA) irreversibly inhibited high threshold Ba2+ currents by 66% and blocked the inhibitory effect of DAMGO or DPDPE. In contrast, the L-type Ca2+ channel blocker nifedipine inhibited high threshold Ba2+ currents by 15% and failed to block the inhibitory effect of DAMGO or DPDPE. These results demonstrate that mu and delta opioid receptors are negatively coupled to N-type Ca2+ channels via PTX- and NEM-sensitive GTP-binding proteins in F-11 cells.

Publication types

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

MeSH terms

  • Analgesics / pharmacology
  • Analgesics, Opioid / pharmacology
  • Animals
  • Barium / metabolism*
  • Barium / pharmacology
  • Calcium / metabolism
  • Calcium Channel Blockers / pharmacology
  • Dose-Response Relationship, Drug
  • Enkephalin, Ala(2)-MePhe(4)-Gly(5)-
  • Enkephalin, D-Penicillamine (2,5)-
  • Enkephalins / pharmacology
  • Ethylmaleimide / pharmacology
  • Gene Expression Regulation / drug effects
  • Hybrid Cells / chemistry
  • Hybrid Cells / drug effects
  • Hybrid Cells / physiology*
  • Ion Channel Gating / drug effects
  • Mice
  • Neuroblastoma
  • Patch-Clamp Techniques
  • Peptides / pharmacology
  • Pertussis Toxin
  • RNA, Messenger / analysis
  • Rats
  • Receptors, Opioid / agonists
  • Receptors, Opioid / genetics
  • Receptors, Opioid / metabolism*
  • Receptors, Opioid, delta / agonists
  • Receptors, Opioid, delta / genetics
  • Receptors, Opioid, delta / metabolism
  • Receptors, Opioid, kappa / agonists
  • Receptors, Opioid, kappa / genetics
  • Receptors, Opioid, kappa / metabolism
  • Receptors, Opioid, mu / agonists
  • Receptors, Opioid, mu / genetics
  • Receptors, Opioid, mu / metabolism
  • Sulfhydryl Reagents / pharmacology
  • Virulence Factors, Bordetella / pharmacology
  • omega-Conotoxin GVIA

Substances

  • Analgesics
  • Analgesics, Opioid
  • Calcium Channel Blockers
  • Enkephalins
  • Peptides
  • RNA, Messenger
  • Receptors, Opioid
  • Receptors, Opioid, delta
  • Receptors, Opioid, kappa
  • Receptors, Opioid, mu
  • Sulfhydryl Reagents
  • Virulence Factors, Bordetella
  • Enkephalin, Ala(2)-MePhe(4)-Gly(5)-
  • Barium
  • Enkephalin, D-Penicillamine (2,5)-
  • omega-Conotoxin GVIA
  • Pertussis Toxin
  • Ethylmaleimide
  • Calcium