NMDA-induced whole-cell currents and single channel conductances in tectal neurons during two stages of early development of chicken.
In cultured tectal neurons of embryonic chicken N-methyl-D-aspartate (NMDA) receptor currents were investigated during two stages of development. Stage I tectal cells were cultivated for 1-5 days from embryonic day 6 or 7, and stage II tectal cells for 10-30 days. Steady state inward currents induced by NMDA were usually several times smaller in tectal cells of stage I than in tectal cells of stage II. At the somata of stage I tectal cells, NMDA-activated single channels with a mean conductance of about 55 pS could be recorded. In tectal cells of stage II, however, NMDA receptor channels were predominantly observed at cellular processes and a mean single channel conductance of about 72 pS was found. Our results suggest changes in regional distribution and function of NMDA receptors during early embryogenesis in the chicken tectum.
Föhr
K J
KJ
Naturwissenschaftiches und Medizinisches Institut, Universität Tübingen, Reutlingen, Germany.
Schirm
T
T
Finger
W
W
D000818:Animals; D002478:Cells, Cultured; D002642:Chick Embryo; D005998:Glycine / Q000494:pharmacology; D016202:N-Methylaspartate / Q000494:pharmacology*; D018408:Patch-Clamp Techniques; D016194:Receptors, N-Methyl-D-Aspartate / Q000502:physiology*; D003336:Tectum Mesencephali / Q000502:physiology*
D016194:Receptors, N-Methyl-D-Aspartate; D016202:N-Methylaspartate; D005998:Glycine