Premium
Localization of [ 3 H]nicotine, [ 3 H]cytisine, [ 3 H]epibatidine, and [ 125 I]α‐bungarotoxin binding sites in the brain of Macaca mulatta
Author(s) -
Han ZhiYan,
Zoli Michele,
Cardona Ana,
Bourgeois JeanPierre,
Changeux JeanPierre,
Le Novère Nicolas
Publication year - 2003
Publication title -
journal of comparative neurology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.855
H-Index - 209
eISSN - 1096-9861
pISSN - 0021-9967
DOI - 10.1002/cne.10659
Subject(s) - epibatidine , cytisine , subiculum , biology , dentate gyrus , interpeduncular nucleus , neuroscience , hippocampal formation , nicotine , habenula , nicotinic agonist , nicotinic acetylcholine receptor , biochemistry , midbrain , central nervous system , receptor
Abstract We determined the localization of [ 3 H]nicotine, [ 3 H]cytisine, [ 3 H]epibatidine, and [ 125 I]α‐bungarotoxin binding sites in the brain of rhesus monkey by means of receptor autoradiography. The labelings by [ 3 H]nicotine, [ 3 H]cytisine, and [ 3 H]epibatidine were highly concordant, except for epibatidine. Layer IV of some cortical areas, most thalamic nuclei, and presubiculum displayed high levels of labeling for the three ligands. Moderate levels of binding were detected in the subiculum, the septum, and the mesencephalon. Low levels were present in layers I–II and VI of the cortex, the cornu Ammonis, the dentate gyrus, and the amygdala. In addition, the level of epibatidine labeling was very high in the epithalamic nuclei and the interpeduncular nucleus, whereas labeling by nicotine and cytisine was very weak in the same regions. The distribution of [ 125 I]α‐bungarotoxin binding differed from the binding of the three agonists. The labeling was dense in layer I of most cortical areas, dentate gyrus, stratum lacunosum‐moleculare of CA1 field, several thalamic nuclei, and medial habenula. A moderate labeling was found in layers V and VI of the prefrontal and frontal cortices, layer IV of primary visual cortex, amygdala, septum, hypothalamus, and some mesencenphalic nuclei. A weak signal was also detected in subiculum, claustrum, stratum oriens, and stratum lucidum of cornu Ammonis and also in some mesencephalic nuclei. The distribution of nicotine, cytisine, and epibatidine bindings corresponds broadly to the patterns observed in rodents, with the marked exception of the epithalamus. However, in monkey, those distributions match the distribution of α2 messenger RNA, rather than that of α4 transcripts as it exists in rodent brains. The distribution of the binding sites for α‐bungarotoxin is larger in the brain of rhesus monkeys than in rodent brain, suggesting a more important role of α7 receptors in primates. J. Comp. Neurol. 461:49–60, 2003. © 2003 Wiley‐Liss, Inc.