Endogenous @entity112 in the medial septum-diagonal band complex increases the release of acetylcholine from the hippocampus: a dual-probe microdialysis study in the freely moving XXXX .

@entity4444 @entity45421 @entity1022 @entity5019 @entity1617 @entity112 @entity35 @entity13686 @entity10448 @entity10449
The effects of histaminergic ligands on both ACh spontaneous release from the hippocampus and the expression of @entity5019 in the medial septum-diagonal band (MSA-DB) of freely moving @entity35 were investigated. Because the majority of cholinergic innervation to the hippocampus is provided by MSA-DB neurons, we used the dual-probe microdialysis technique to apply drugs to the MSA-DB and record the induced effects in the projection area. Perfusion of MSA-DB with high-KCl medium strongly stimulated hippocampal ACh release which, conversely, was significantly reduced by intra-MSA-DB administration of @entity1022 . @entity112 or the H2 receptor agonist dimaprit, applied directly to the hippocampus, failed to alter ACh release. Conversely, perfusion of MSA-DB with these two compounds increased ACh release from the hippocampus. Also, @entity13686 and @entity10449 , two H3 receptor antagonists, administered into MSA-DB, increased the release of hippocampal ACh, whereas @entity10448 , an H3 receptor agonist, produced the opposite effect. The blockade of MSA-DB H2 receptors, caused by local perfusion with the H2 receptor antagonist @entity4444 , moderated the spontaneous release of hippocampal @entity1617 and antagonized the facilitation produced by H3 receptor antagonists. @entity45421 , an H1 receptor antagonist, was without effect. Moreover, cells expressing @entity5019 immunoreactivity were significantly more numerous in ciproxifan- or @entity13686 -treated @entity35 than in controls, although no colocalization of anti- @entity5019 and anti-ChAT immunoreactivity was observed. These results indicate a role for endogenous @entity112 in modulating the cholinergic tone in the hippocampus.
