OFF pathway is preferentially suppressed by the activation of GABA(A) receptors in carp retina.
This study examines the effect of gamma-aminobutyric acid (GABA) on the ON and OFF pathways in isolated, superfused carp retina. In most (76%) of amacrine cells bath-applied GABA preferentially suppressed the OFF response. The effect of GABA was blocked by bicuculline. Baclofen did not cause a similar effect. Furthermore, GABA produced a substantial suppression of the OFF bipolar cell response. We conclude that the preferential suppression of the OFF pathway may be due to a presynaptic inhibition mediated via GABA(A) receptors at the terminals of OFF bipolar cells.
Zhang
D Q
DQ
Shanghai Institute of Physiology, Chinese Academy of Sciences.
Yang
X L
XL
D000818:Animals; D001418:Baclofen / Q000494:pharmacology; D001640:Bicuculline / Q000494:pharmacology; D002347:Carps / Q000502:physiology*; D018755:GABA Agonists / Q000494:pharmacology; D018756:GABA Antagonists / Q000494:pharmacology; D066298:In Vitro Techniques; D009433:Neural Inhibition; D009434:Neural Pathways / Q000187:drug effects / Q000502:physiology; D011963:Receptors, GABA-A / Q000502:physiology*; D012160:Retina / Q000166:cytology / Q000187:drug effects / Q000502:physiology*; D005680:gamma-Aminobutyric Acid / Q000494:pharmacology
D018755:GABA Agonists; D018756:GABA Antagonists; D011963:Receptors, GABA-A; D005680:gamma-Aminobutyric Acid; D001418:Baclofen; D001640:Bicuculline