Evidence for the existence of α- and β-adrenoceptors on cultured glial cells—an electrophysiological study

doi:10.1016/0306-4522(82)90109-9

Neuroscience

Volume 7, Issue 11, November 1982, Pages 2867-2872

https://doi.org/10.1016/0306-4522(82)90109-9 Get rights and content

Abstract

The action of adrenergic α- and β-agonists and antagonists has been studied on the membrane potential and resistance of glial cells of cultured rat central nervous system. Noradrenaline and the α-adrenoceptor stimulating agents phenylephrine and clonidine (10⁻⁷ to 10⁻⁴ M) depolarized the glial membrane, whereas the β-agonist isoprenaline caused a hyperpolarization at low concentrations (10⁻⁷ and 10⁻⁶ M). The effects of noradrenaline and phenylephrine were reversibly blocked by the α-antagonist phentolamine, whereas those of isoprenaline were antagonized by the β-blocker atenolol. Atenolol did not affect the depolarization by noradrenaline. The glial depolarization induced by the α-agonists was not the consequence of a change in the extracellular K⁺-concentration unlike that produced by amino acid transmitters.

The present results, together with those of biochemical and autoradiographic binding studies, suggest that α- and β-adrenoceptors occur on glial cells and that the glial depolarization is mediated by α-receptors, whereas the hyperpolarization is due to activation of β-receptors.

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Evidence for the existence of α- and β-adrenoceptors on cultured glial cells—an electrophysiological study

Abstract

Neuroscience

Brain Res.

Brain Res.

Eur. J. Pharmac.

Neuroscience Letters

Neuroscience

Expl Neurol.

Brain Res.

(−)-[125I]-Iodopindolol, a new highly selective radioiodinated β-adrenergic receptor antagonist: measurement of β-receptors on intact rat astrocytoma cells

J. Cyclic. Nucl. Res.

The pharmacology of adrenergic neuronal responses in the cerebral cortex: evidence for excitatory α- and inhibitory β-receptors

Br. J. Pharmac.

α1 and α2 adrenergic receptors in mouse brain astrocytes from primary cultures

J. Neurosci. Res.

Effects of tetraethylammonium chloride on contractile, membrane and cable properties of rabbit artery muscle

J. Physiol., Lond.

(−)-[¹²⁵I]-Iodopindolol, a new highly selective radioiodinated β-adrenergic receptor antagonist: measurement of β-receptors on intact rat astrocytoma cells

α₁ and α₂ adrenergic receptors in mouse brain astrocytes from primary cultures