Summary of modulatory neurotransmitters
The activation of many different receptors subtypes is capable of abolishing the generation of spindle waves and promoting the generation of single spike activity. This transition is similar to that associated with moving from slow wave sleep to waking or REM sleep.
In thalamocortical relay cells the activation of muscarinic, alpha-1 adrenergic, H1-histaminergic, or glutamate metabotropic receptors results in the reduction of a leak potassium current and the depolarization of the cell. In addition, the activation of beta-adrenergic, serotoninergic, and H2-histaminergic receptors results in the abolition of spindle waves through the enhancement of the H-current.
In Perigeniculate neurons, the activation of alpha1-adrenoceptors, serotoninergic-2 (or 1C) receptors, or glutamate metabotropic receptors results in the depolarization of these cells and a block of spindle wave generation.
McCormick, D.A. and Wang, Z. Serotonin and noradrenaline excite GABAergic neurones of the guinea-pig and cat nucleus reticularis thalami. Journal of Physiology (1991) 442: 235-255.
McCormick, D.A. Neurotransmitter actions in the thalamus and cerebral cortex and their role in neuromodulation of thalamocortical activity. Progress in Neurobiology (1992) 39: 337-388.
Lee, K., and McCormick, D.A. (1996) Abolition of spindle oscillations by serotonin and norepinephrine in the lateral geniculate and perigeniculate nuclei in vitro. Neuron 17: 309-321.