Excitatory amino acid receptors on sustained retinal ganglion cells in the kitten during the critical period of development.

Abstract

Effects of iontophoretically applied excitatory amino acid analogues, kainate, quisqualate and N-methyl-D-aspartate (NMDA) and their receptor antagonists on the sustained class of retinal ganglion cells were studied in the optically intact eye of pentobarbitone-anaesthetized kittens (7-9 weeks of age). These results were compared with the effects obtained in adult cats. All 3 excitatory amino acid agonists had excitatory actions on the majority of On- and Off-sustained ganglion cells in the kitten but at higher current levels than those required for adult cells, suggesting all 3 types of receptors of weaker sensitivity are present on the kitten cells. Whilst the relative potency of kainate, quisqualate and NMDA was 15:3:1 in the adult cells, it was 5:2:1 in the kitten cells. As for other neurones in the CNS, an increase in the potency of kainate receptors and a decrease in that of NMDA receptors appear, therefore, to characterize the postnatal development of the excitatory amino acid receptors on the retinal ganglion cells. In accordance with the agonist results, a broadband receptor antagonist, kynurenate, powerfully antagonised responses of kitten cells as well as those of adult cells. The pure NMDA receptor antagonist, 3((+-)-2-carboxypiperazin-4-yl)propyl-1-phosphonate (CPP), however, only suppressed spontaneous firing of kitten cells. Furthermore, in kitten cells, the visually-driven firing was depressed while the level of firing was raised by these excitatory amino acid analogous, and a long period of inhibition of firing followed the agonist-induced excitation.(ABSTRACT TRUNCATED AT 250 WORDS)

• Authors: H Ikeda, J Robbins, C D Kay
• Journal: Brain research. Developmental brain research (Brain Res Dev Brain Res) Vol. 51 Issue 1 Pg. 85-91 (Jan 01 1990) ISSN: 0165-3806 [Print] Netherlands
• PMID: 2153481 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Oxadiazoles
• Receptors, Amino Acid
• Receptors, Cell Surface
• Aspartic Acid
• N-Methylaspartate
• Quisqualic Acid
• Kainic Acid

Topics

• Action Potentials (drug effects)
• Aging (physiology)
• Animals
• Aspartic Acid (analogs & derivatives, pharmacology)
• Cats
• Kainic Acid (pharmacology)
• N-Methylaspartate
• Oxadiazoles (pharmacology)
• Photic Stimulation
• Quisqualic Acid
• Receptors, Amino Acid
• Receptors, Cell Surface (drug effects, physiology)
• Retina (physiology)
• Retinal Ganglion Cells (drug effects, physiology)
• Visual Pathways (physiology)