Quantitative autoradiography of 5-HT_1A and 5-HT_1B receptors in various brain regions.

<p>(<b><i>A</i></b>) Representative photomicrographs of autoradiograms following the binding of [³H]WAY100635 to 5-HT_1A receptors on whole coronal sections. The signal was visibly increased in e.g. the dorsal raphe, CA1 of hippocampus, frontal cortex and septum of <i>Tph2</i>−/− mice. (<b><i>B</i></b>) Binding density of 5-HT_1A receptors labeled by the radioligand [³H]WAY100635 was up-regulated in most of the brain regions of <i>Tph2</i>−/− mice. (<b><i>C</i></b>) 5-HT_1A receptor-mediated increase in [³⁵S]GTP-γ-S binding after stimulation revealed enhanced 5-HT_1A coupling in the frontal cortex and septum of <i>Tph2</i>−/− mice. (<b><i>D</i></b>) Binding density of 5-HT_1B receptors labeled by the radioligand [¹²⁵I]ICYP was also increased in some brain regions of <i>Tph2</i>−/− mice. For (<b><i>B, C, D</i></b>) results are expressed as optical density (OD = specific OD – nonspecific OD) and presented as means ± sem (n = 5). * indicates ANOVA significant output for genotype effect with *p<0.05, **p<0.01, ***p<0.001. For detailed statistical results see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0043157#pone.0043157.s001" target="_blank">Table S1</a>. c: cortex, Ss: somatosensory, Retrospl.: retrosplenial, CA1: cornu ammonis area 1 of hippocampus, g: gyrus, D: dorsal, Enth.: enthorinal, Caud. put.: caudate putamen, V pal.: ventral pallidus, Globus pal.: globus pallidus, Hypo. lat.: lateral hypothalamus, D subic.: dorsal subicullum, Subst. nigra: substantia nigra.