Neuronal subpopulations in the suprachiasmatic nuclei based on their response to retinal and intergeniculate leaflet stimulation.
In order to characterize how suprachiasmatic nuclei (SCN) neurons integrate its visual inputs, extracellular responses from SCN and adjacent hypothalamic neurons were recorded after stimulation of either the retina, the intergeniculate leaflet (IGL) or both simultaneously. Individual stimulation of either structure elicited excitatory or inhibitory responses in 36% of SCN and 20% of non-SCN neurons. Three subpopulations of SCN neurons were found, the first two responding exclusively either to the retina or the IGL, and the third responding to both the retina and the IGL. Simultaneous stimulation of the retina and the IGL induced a change in the firing pattern of some SCN neurons, which suggests modulatory regulation of SCN neuronal activity by synaptic interactions between its visual inputs.
Roig
J A
JA
Departamento de Fisiología, Facultad de Medicina, Universidad Nacional Autónoma de México, México D.F., Mexico.
Granados-Fuentes
D
D
Aguilar-Roblero
R
R
D000200:Action Potentials; D000818:Animals; D001931:Brain Mapping; D004558:Electric Stimulation; D005829:Geniculate Bodies / Q000502:physiology*; D008297:Male; D009474:Neurons / Q000166:cytology / Q000502:physiology*; D010775:Photic Stimulation; D051381:Rats; D017208:Rats, Wistar; D012160:Retina / Q000502:physiology*; D013493:Suprachiasmatic Nucleus / Q000166:cytology / Q000502:physiology*; D014796:Visual Perception