Dopaminergic modulation of photopic temporal transfer properties in goldfish retina investigated with the ERG.
The influence of dopamine (DA) through either D1- or D2-dopamine receptors (D1-/D2-R) onto temporal transfer properties of the retina has been investigated using the ERG. Single flash responses and flicker responses were measured in the vitreous under photopic illumination conditions after application of either D1-/D2-R agonists or antagonists. All DA-R drugs did change the single flash responses, but only blockade of D2-R or activation of D1-R also changed the temporal transfer properties. In the Bode plot the gain characteristic was changed and thereby the upper limit frequency reduced. The action of DA is discussed on the base of a membrane resonance model in the outer retina versus a feed-forward inhibition model in the inner retina.
Mora-Ferrer
Carlos
C
Inst. Zoologie, Abt. III, J. Gutenberg Universität, Colonel Kleinmann Weg 2, SB II 55099 Mainz, Germany. carlos.mora-ferrer@uni-mainz.des
Behrend
Konstantin
K
D015647:2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benzazepine / Q000494:pharmacology; D000221:Adaptation, Ocular / Q000502:physiology; D000818:Animals; D001224:Aspartic Acid / Q000494:pharmacology; D001552:Benzazepines / Q000494:pharmacology; D004298:Dopamine / Q000502:physiology*; D018491:Dopamine Agonists / Q000494:pharmacology; D018492:Dopamine Antagonists / Q000494:pharmacology; D004596:Electroretinography / Q000379:methods; D006054:Goldfish / Q000502:physiology*; D008954:Models, Biological; D010786:Photoreceptor Cells / Q000187:drug effects / Q000502:physiology; D019257:Quinpirole / Q000494:pharmacology; D017447:Receptors, Dopamine D1 / Q000502:physiology; D017448:Receptors, Dopamine D2 / Q000502:physiology; D012160:Retina / Q000187:drug effects / Q000502:physiology*; D013469:Sulpiride / Q000494:pharmacology
D001552:Benzazepines; D018491:Dopamine Agonists; D018492:Dopamine Antagonists; D017447:Receptors, Dopamine D1; D017448:Receptors, Dopamine D2; D019257:Quinpirole; D001224:Aspartic Acid; D015647:2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benzazepine; D013469:Sulpiride; D004298:Dopamine