Sensory presynaptic and widespread somatodendritic immunolocalization of central ionotropic P2X ATP receptors

doi:10.1016/S0306-4522(97)00365-5

Neuroscience

Volume 83, Issue 1, 1998, Pages 177-190

https://doi.org/10.1016/S0306-4522(97)00365-5 Get rights and content

Abstract

Recent evidence suggests that extracellular ATP plays a neurotransmitter role in the central nervous system. Its fast ionotropic effects are exerted through a family of P2X ATP-gated channels expressed in brain and spinal cord. To determine the physiological significance of central ATP receptors, we have investigated the localization of a major neuronal P2X receptor at the cellular and subcellular levels using affinity-purified antibodies directed against the C-terminal domain of P2X₄ subunit. Subunit-specific anti-P2X₄ antibodies detected a single band of 57, 000±3000 mol. wt in transfected HEK-293 cells and in homogenates from adult rat brain. The strongest expression of central P2X receptors was observed in the olfactory bulb, lateral septum, cerebellum and spinal cord. P2X₄ immunoreactivity was also evident in widespread areas including the cerebral cortex, hippocampus, thalamus and brainstem. In all regions examined, P2X receptors were associated with perikarya and dendrites where they were concentrated at the level of afferent synaptic junctions, confirming a direct involvement of postsynaptic ATP-gated channels in fast excitatory purinergic transmission.

Moreover, P2X₄ containing purinoceptors were localized in axon terminals in the olfactory bulb and in the substantia gelatinosa of nucleus caudalis of the medulla and dorsal horn of the spinal cord, demonstrating an important selective presynaptic role of ATP in the modulation of neurotransmitter release in central sensory systems.

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Sensory presynaptic and widespread somatodendritic immunolocalization of central ionotropic P2X ATP receptors

Abstract

Fedn Ear. biochem. Socs Lett.

Brain Res.

Cell

Neuron

Nature

Soc. Neurosci. Abstr.

Naunyn-Schmiedebergs Arch. Pharmac.

J. Cell Sci.

Autoradiography of P2x ATP receptors in the rat brain

Br. J. Pharmac.

Distribution of [3H]α, β-methylene ATP binding sites in rat brain and spinal cord

NeuroReport

New structural motif for ligand-gated ion channels defined by an ionotropic ATP receptor

Nature

P2X receptors: an emerging channel family

Eur. J. Neurosci.

An antagonist-insensitive P2X receptor expressed in epithelia and brain

Eur. molec. Biol. Org. J.

Zinc-induced collapse of augmented inhibition by GABA in a temporal lobe epilepsy model

Nature

A P2X receptor expressed by a subset of sensory neurons

Nature

Zn2+ potentiates ATP-activated currents in rat sympathetic neurons

Pflügers Arch.

Cloning of P2X5 and P2X6 receptors, and the distribution and properties of an extended family of ATP-gated ion channels

J. Neurosci.

Zinc in maturing rat brain: hippocampal concentration and localization

J. Neurochem.

ATP-induced inward current in neurons freshly dissociated from the tuberomammilary nucleus

J. Neurophysiol.

Is ATP a central synaptic mediator for certain primary afferent fibers from mammalian brain?

Molecular cloning and functional expression of a novel rat heart P2X purinoceptor

Fedn Eur. biochem. Socs Lett.

Distribution of [³H]α, β-methylene ATP binding sites in rat brain and spinal cord

Zn²⁺ potentiates ATP-activated currents in rat sympathetic neurons