Differential G protein-mediated coupling of D2 dopamine receptors to K+ and Ca2+ currents in rat anterior pituitary cells

doi:10.1016/0896-6273(92)90273-G

Neuron

Volume 8, Issue 3, March 1992, Pages 455-463

https://doi.org/10.1016/0896-6273(92)90273-G Get rights and content

Abstract

In anterior pituitary cells, dopamine, acting on D₂ dopamine receptors, concomitantly reduces calcium currents and increases potassium currents. These dopamine effects require the presence of intracellular GTP and are blocked by pretreatment of the cells with pertussis toxin, suggesting that one or more G protein is involved. To identify the G proteins involved in coupling D₂ receptors to these currents, we performed patch-clamp recordings in the whole-cell configuration using pipettes containing affinity-purified polyclonal antibodies raised against either G_oα, G_3α, or G_i1,2α. Dialysis with G_oα antiserum significantly reduced the inhibition of calcium currents induced by dopamine, while increase of potassium currents was markedly attenuated only by G_i3α antiserum. We therefore conclude that in pituitary cells, two different G proteins are involved in the signal transduction mechanism that links D₂ receptor activation to a specific modulation of the four types of ionic channels studied here.

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^†: Present address: Institut A. Fessard, CNRS, 91198 Gif-sur-Yvette, France.

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Neuron

ArticleDifferential G protein-mediated coupling of D2 dopamine receptors to K+ and Ca2+ currents in rat anterior pituitary cells

Abstract

Biochim. Biophys. Acta

J. Biol. Chem.

J. Biol. Chem.

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Neuron

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FEBS Lett.

J. Biol. Chem.

J. Biol. Chem.

Trends Pharmacol.

Neurosci. Lett.

Trends Neurosci.

Trends Pharmacol.

Dopamine: a prolactin-inhibiting hormone

Endocr. Rev.

Immunocytochemical localization of the guanine nucleotide-binding protein Go in primary cultures of neuronal and glial cells

J. Neurosci.

Neuroblastoma differentiation involves the expression of two isoforms of the α-subunit of Go

J. Neurochem.

Metabolism of two Go α isoforms in neuronal cells during differentiation

J. Biol. Chem.

Ionic channels and their regulation by G protein subunits

Annu. Rev. Physiol.

G-proteins and potassium currents in neurons

Annu. Rev. Physiol.

Antibodies to the GTP-binding protein Go attenuate the inhibition of the calcium current by noradrenaline in mouse neuroblastoma × rat glioma (NG 108-15) hybrid cells

J. Physiol.

The inhibition of phosphatidylinositol turnover: a possible post receptor mechanism for the prolactin secretion-inhibiting effect of dopamine

Endocrinology

Multiple transduction mechanisms of dopamine, somatostatin and angiotensin II receptors in anterior pituitary cells

Horm. Res.

Pharmacological characterization of the D2 dopamine receptors negatively coupled with adenylate cyclase in rat anterior pituitary

Mol. Pharmacol.

Guanine nucleotide-binding protein Go-induced coupling of neuropeptide Y receptors to calcium channels in sensory neurons

Dopamine receptors on intact anterior pituitary cells in culture: functional association with the inhibition of prolactin and thyrotropin

Endocrinology

Article
Differential G protein-mediated coupling of D₂ dopamine receptors to K⁺ and Ca²⁺ currents in rat anterior pituitary cells

Immunocytochemical localization of the guanine nucleotide-binding protein G_o in primary cultures of neuronal and glial cells

Neuroblastoma differentiation involves the expression of two isoforms of the α-subunit of G_o

Metabolism of two G_o α isoforms in neuronal cells during differentiation

Antibodies to the GTP-binding protein G_o attenuate the inhibition of the calcium current by noradrenaline in mouse neuroblastoma × rat glioma (NG 108-15) hybrid cells

Pharmacological characterization of the D₂ dopamine receptors negatively coupled with adenylate cyclase in rat anterior pituitary

Guanine nucleotide-binding protein G_o-induced coupling of neuropeptide Y receptors to calcium channels in sensory neurons