Differences in Response to Serotonergic Activation between First and Higher Order Thalamic Nuclei

AUTOR(ES)

Varela, C.

FONTE

Oxford University Press

RESUMO

Two types of thalamic nuclei have been recognized: first order, which relay information from subcortical sources, and higher order, which may relay information from one cortical area to another. We have recently shown that muscarinic agonists depolarize all first order and most higher order relay cells but hyperpolarize a significant proportion of higher order relay cells. We now extend this result to serotonergic agonists, using rat thalamic brain slices and whole-cell, current- and voltage-clamp recordings from relay cells in various first order (the lateral geniculate nucleus, the ventral posterior nucleus, and the ventral portion of the medial geniculate body) and higher order nuclei (the lateral posterior, the posterior medial nucleus, and the dorsal portion of the medial geniculate body). Similar to the effects of muscarinic agonists, we found that first and most higher order relay cells were depolarized by serotonergic agonists, but 15% of higher order relay cells responded with hyperpolarization. Thus different subsets of higher order relay cells are hyperpolarized by these modulatory systems, which could have implications for the transfer of information between cortical areas.

Documentos Relacionados

• Higher-order thalamic relays burst more than first-order relays
• Behavioral correlates of the activity of serotonergic and non-serotonergic neurons in caudal raphe nuclei
• Noradrenergic and serotonergic modulation of a hyperpolarization-activated cation current in thalamic relay neurones.
• Corrections to the entropy in higher order gravity
• Higher order chromatin structures in maize and Arabidopsis.