Serotoninergic innervation of thalamic trigeminovascular neurons.

<p><u>Left</u>: Immunopositive Serotonin Transporter axons (green) surrounding a thalamic dura-sensitive neuron (red) labeled with TMR–dextran. Nuclear counterstaining was performed with DAPI (blue). Arrowheads indicate close apposition of SERT positive axons and the cell body and dendrites of the labeled neuron. <u>Upper right</u>: Location of the dura-sensitive neuron (red star) shown at left. Number in red indicates distance from <i>bregma</i> (mm). Scale bars = 100 µm. Since SERT does not stain cell somas, it was not possible to use this marker to identify the serotoninergic neurons in the raphe nuclei that project to the thalamic nuclei containing trigeminovascular neurons. Abbreviations: Hb, habenula; MD, mediodorsal thalamic; CL, centrolateral thalamic.