Effects of glutamic acid and related agents on horizontal cells in a marine teleost retina.
Excitatory amino acids (EAAs) such as glutamic and aspartic acids, considered as the most likely neurotransmitters at the photoreceptor-horizontal cell synapse of teleost retinas, as well as agonists such as kainic acid and several of their antagonists, were applied to isolated and superfused retinas of the teleost Eugerres plumieri. Intracellular recordings from horizontal cells reveal that EAA receptors are of the kainate-quisqualate type. There is competitive inhibition between the agonist and antagonist agents used, and under their combined effect, the synapse under study remains operational, in a functional state, able to modulate the horizontal cell membrane potential upon retinal illumination.
Laufer
M
M
Center of Biophysics and Biochemistry, IVIC, Caracas, Venezuela.
Negishi
K
K
Salas
R
R
D000818:Animals; D001224:Aspartic Acid / Q000494:pharmacology; D003623:Dark Adaptation / Q000187:drug effects / Q000502:physiology; D018690:Excitatory Amino Acid Agonists / Q000494:pharmacology; D018691:Excitatory Amino Acid Antagonists / Q000494:pharmacology; D005399:Fishes / Q000502:physiology*; D018698:Glutamic Acid / Q000494:pharmacology*; D066298:In Vitro Techniques; D007736:Kynurenic Acid / Q000494:pharmacology; D008564:Membrane Potentials / Q000187:drug effects / Q000502:physiology; D010786:Photoreceptor Cells / Q000187:drug effects; D011810:Quinoxalines / Q000494:pharmacology; D017470:Receptors, Glutamate / Q000187:drug effects / Q000378:metabolism; D012160:Retina / Q000166:cytology* / Q000187:drug effects
D018690:Excitatory Amino Acid Agonists; D018691:Excitatory Amino Acid Antagonists; D011810:Quinoxalines; D017470:Receptors, Glutamate; D001224:Aspartic Acid; D018698:Glutamic Acid; C056723:FG 9041; D007736:Kynurenic Acid