[Spontaneous rhythmic depolarization in the principal cells of the lateral geniculate body in vitro: the role of NMDA receptors].
Intracellular recordings using standard current clamp techniques were performed on projection cells of the rat lateral geniculate nucleus (LGN) in vitro. These cells are generally quiescent in vitro but when magnesium was removed from the perfusion medium they invariably showed rhythmic depolarizations (15-20 mV, 210-320 ms) that occurred at a frequency of 1.5-2 Hz and evoked 1 to 4 action potentials. This activity was completely blocked by micromolar concentrations of magnesium (50-150 microM) while tetrodotoxine (1 microM) abolished the action potentials but left the underlying rhythmic depolarizations unchanged. These results demonstrate that rat LGN projection cells are capable of producing rhythmic depolarizations in vitro and suggest the possibility that NMDA receptors might be involved in these rhythmic oscillations.
Haby
M
M
Institut des Neurosciences du C.N.R.S., Université Pierre-et-Marie-Curie, Paris.
Leresche
N
N
Jassik-Gerschenfeld
D
D
Soltesz
I
I
Crunelli
V
V
D000200:Action Potentials / Q000187:drug effects; D000818:Animals; D005829:Geniculate Bodies / Q000502:physiology*; D008274:Magnesium / Q000494:pharmacology; D051381:Rats; D016194:Receptors, N-Methyl-D-Aspartate; D017981:Receptors, Neurotransmitter / Q000502:physiology*; D013779:Tetrodotoxin / Q000494:pharmacology
D016194:Receptors, N-Methyl-D-Aspartate; D017981:Receptors, Neurotransmitter; D013779:Tetrodotoxin; D008274:Magnesium
Dépolarisations rythmiques spontanées dans les cellules principales du corps genouillé latéral in vitro: rôle des récepteurs NMDA.