Dimethoxyaporphine as an antagonist of chemical excitation in the pigeon optic tectum

doi:10.1016/0304-3940(77)90182-3

Neuroscience Letters

Volume 4, Issue 6, May 1977, Pages 347-350

https://doi.org/10.1016/0304-3940(77)90182-3 Get rights and content

Abstract

The alkaloid l-5,6-dimethoxyaporphine (l-nuciferine) was studied with iontophoretic techniques, and its interaction with excitant amino acids on neurones of the pigeon optic tectum was tested. This compound antagonizes the action of l-glutamate and, to a weaker extent, that of l-aspartate and d,l-homocysteate. In comparison, l-5,6-dimethoxyaporphine did not reduce the acetylcholine evoked excitation.

References (13)

P.M. Beart
An evaluation of l-glutamate as the transmitter released from optic nerve terminals of the pigeon
Brain Res.
(1976)
D.R. Curtis et al.
Excitation of mammalian central neurones by acidic amino acids
Brain Res.
(1972)
J. Davies et al.
Microelectrophoretic studies on the depressant action of HA-966 on chemically and synaptically excited neurones in the cat cerebral cortex and cuneate nucleus
Brain Res.
(1973)
S. Haldeman et al.
The antagonistic action of glutamic acid diethylester towards amino acid-induced and synaptic excitation of central neurones
Brain Res.
(1972)
Y. Ben-Ari et al.
Specificity of nuciferine as an antagonist of amino acid and synaptically evoked activity in cells of the feline thalamus
J. Physiol. (Lond.)
(1975)
A.W. Duggan et al.
Effect of nuciferine on the chemical excitation of Renshaw cells in the rat
Arch. int. Pharmacodyn.
(1973)

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Dimethoxyaporphine as an antagonist of chemical excitation in the pigeon optic tectum

Abstract

Brain Res.

Brain Res.

Brain Res.

Brain Res.

Specificity of nuciferine as an antagonist of amino acid and synaptically evoked activity in cells of the feline thalamus

J. Physiol. (Lond.)

Effect of nuciferine on the chemical excitation of Renshaw cells in the rat

Arch. int. Pharmacodyn.