Inhibition of calcium currents in cultured myenteric neurons by neuropeptide Y: evidence for direct receptor/channel coupling

doi:10.1016/0006-8993(90)91751-2

Brain Research

Volume 532, Issues 1–2, 5 November 1990, Pages 120-130

https://doi.org/10.1016/0006-8993(90)91751-2 Get rights and content

Abstract

Single channel recordings from rat myenteric plexus neurons demonstrated the presence of two categories of Ca²⁺ channels. One type of Ca channel had a slope conductance of 27 pS and was sensitive to dihydropyridines while the other type had a conductance of 14 pS and was dihydropyridine-insensitive. The 14 pS channel was mostly inactivated at a holding potential of -40 mV, while the 27 pS channel was much more resistant to depolarized holding potentials. A majority of whole-cell current was reprinted by the use of negative holding (-90 mV) potentials, when compared to that obtained at a holding potential of -40 mV. These properties are consistent with N- and L-type Ca channels previously described. In general, the inactivating part of the whole-cell Ca²⁺ current, selectively reprimed by negative holding potentials, was inhibited by neuropeptide Y (NPY). Depolarization-induced [Ca²⁺]_i transients assessed using fura-2 showed that the inhibitory effects of nitrendipine and NPY were additive. The effects of NPY were abolished by pertussis toxin pretreatment. Single-channel experiments showed that neither the 14 nor the 27 pS Ca channel currents were inhibited by the addition of NPY outside the patch pipette. These results suggest that NPY modulates N-type Ca²⁺ channels selectively in these neurons and that an easily diffusible second messenger does not appear to participate in receptor/channel coupling.

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Inhibition of calcium currents in cultured myenteric neurons by neuropeptide Y: evidence for direct receptor/channel coupling

Abstract

Biochem. Biophys. Res. Commun.

Neuron

Trends Biochem. Sci.

Biochem. Biophys. Res. Commun

Trends Neurosci.

J. Biol. Chem.

Single L-type Ca2+ channels in dorsal root ganglion neurons can be modulated by norepinephrine

Soc. Neurosci. Abstract

Classes of calcium channels in vertebrate cells

Ann. Rev. Physiol.

Uncoupling of cardiac muscarinic and β-adrenergic receptors from ion channels by a guanine nucleotide analogue

Nature (Lond.)

Neuropeptide Y action in the rat hippocampal slice site and mechanism of presynaptic inhibition

J. Neurosci.

The effect of protein kinase C down-regulation on the inhibitory modulation of dorsal root ganglion neuron Ca2+ currents by neuropeptide Y

Neurosci.

Go induced coupling of NPY receptors to calcium channels in sensory neurons

Noradrenaline modulates calcium channels through tight receptor channel coupling

J. Physiol. (Lond.)

Kinetic and pharmacological properties distinguish three types of calcium currents in chick sensory neurons

J. Physiol. (Lond.)

Single channel recordings of three types of calcium in chick sensory neurons

J. Physiol. (Lond.)

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Br. J. Pharmacol.

Chemical neuroanatoms and the analysis of neuronal circuitry in the enteric nervous system

Synaptic modulation of calcium-dependent potassium conductances in myenteric neurons of the guinea pig

J. Physiol. (Lond.)

Actions of baclofen on components of the Ca2+ current in rat and mouse dorsal root ganglion neurons in culture

Br. J. Pharmacol.

2-Chloroadenosine reduces the N-type calcium current of cultured mouse sensory neurons in a pertussis toxin-sensitive manner

J. Physiol. (Lond.)

Improved patch-clamp techniques for high-resolution current recording from cells and cell-tree membrane patches

Pflügers Arch.

Calcium channel selectivity for divalent and monovalent cations: voltage-and concentration-dependence of single channel current in guinea pig ventricular heart cells

J. Gen. Physiol.

Dominant role of N-type Ca2+ channels in evoked release of norepinephrine from sympathetic neurons

Science

Single L-type Ca²⁺ channels in dorsal root ganglion neurons can be modulated by norepinephrine

The effect of protein kinase C down-regulation on the inhibitory modulation of dorsal root ganglion neuron Ca²⁺ currents by neuropeptide Y

Actions of baclofen on components of the Ca²⁺ current in rat and mouse dorsal root ganglion neurons in culture

Dominant role of N-type Ca²⁺ channels in evoked release of norepinephrine from sympathetic neurons