Retinal inputs to the optic tectum (TeO) triggered by moving stimuli elicit synchronized feedback signals from two isthmic nuclei: the isthmi parvocelullaris (Ipc) and isthmi semilunaris (SLu). Both of these nuclei send columnar axon terminals back to the same tectal position receiving the retinal input. The feedback signals from the Ipc seem to act as an attentional spotlight by selectively boosting the propagation of retinal inputs from the tectum to higher visual areas. Although Ipc and SLu nuclei are widely considered cholinergic because of their immunoreactivity for choline acetyltransferase (ChAT), contradictory findings, including the expression of the vesicular glutamate transporter 2 (VGluT2) mRNA in Ipc neurons, have raised doubts about the purely cholinergic nature of this nucleus. In this study, in chicks, we revise the neurochemical identity of the isthmic nuclei by using in situ hybridization assays for VGluT2 along with three cholinergic markers: the vesicular acetylcholine transporter (VAChT), the high-affinity choline transporter (CHT1) and ChAT. We found that neurons in the SLu showed strong mRNA expression of all three cholinergic markers, whereas the expression of VAChT mRNA in the Ipc was undetectable in our essays. Instead, Ipc neurons exhibited a strong expression of VGluT2 mRNA. Immunohistochemistry assays showed VGluT2 immunoreactivity in the TeO codistributing with anterogradely labeled Ipc axon-terminal boutons, further supporting a glutamatergic function for the Ipc nucleus. Therefore, our results strongly suggest that, in the chick, whereas the feedback from the SLu to the TeO is indeed cholinergic, the feedback from the Ipc has a marked glutamatergic component.
Pubmed ID: 25594665 RIS Download
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This unknown targets
View all literature mentionsThis monoclonal targets VGlut2
View all literature mentionsThis polyclonal targets Choline Acetyltransferase
View all literature mentionsThis unknown targets Mouse IgG (H+L)
View all literature mentionsThis unknown targets Digoxigenin
View all literature mentionsThis polyclonal secondary targets IgG (H+L)
View all literature mentionsThis polyclonal secondary targets IgG (H+L)
View all literature mentionsThis polyclonal targets IgG
View all literature mentionsDatabase of nucleotide sequences from several sources, including GenBank, RefSeq, TPA and PDB. Genome, gene and transcript sequence data provide the foundation for biomedical research and discovery.
View all literature mentionsA tool to design target-specific primers for polymerase chain reaction (PCR). It uses Primer3 to design PCR primers and then uses BLAST and global alignment algorithm to screen primers against user-selected database in order to avoid primer pairs (all combinations including forward-reverse primer pair, forward-forward as well as reverse-reverse pairs) that can cause non-specific amplifications.
View all literature mentionsThis unknown targets Mouse IgG (H+L)
View all literature mentionsExpression atlas of in situ hybridization images from large collection of genes expressed in brain of adult male zebra finches. Goal of ZEBrA project is to develop publicly available on-line digital atlas that documents expression of large collection of genes within brain of adult male zebra finches.
View all literature mentionsWeb search tool to find regions of similarity between biological sequences. Program compares nucleotide or protein sequences to sequence databases and calculates statistical significance. Used for identifying homologous sequences.
View all literature mentionsThis unknown targets Mouse IgG (H+L)
View all literature mentionsThis unknown targets Mouse IgG (H+L)
View all literature mentionsThis polyclonal secondary targets IgG (H+L)
View all literature mentionsThis polyclonal secondary targets IgG (H+L)
View all literature mentionsThis unknown targets Mouse IgG (H+L)
View all literature mentionsThis monoclonal targets VGlut2
View all literature mentionsThis unknown targets Digoxigenin
View all literature mentionsA tool to design target-specific primers for polymerase chain reaction (PCR). It uses Primer3 to design PCR primers and then uses BLAST and global alignment algorithm to screen primers against user-selected database in order to avoid primer pairs (all combinations including forward-reverse primer pair, forward-forward as well as reverse-reverse pairs) that can cause non-specific amplifications.
View all literature mentionsThis polyclonal secondary targets IgG (H+L)
View all literature mentionsThis polyclonal targets Choline Acetyltransferase
View all literature mentionsThis unknown targets
View all literature mentionsDatabase of nucleotide sequences from several sources, including GenBank, RefSeq, TPA and PDB. Genome, gene and transcript sequence data provide the foundation for biomedical research and discovery.
View all literature mentionsThis polyclonal secondary targets IgG (H+L)
View all literature mentionsExpression atlas of in situ hybridization images from large collection of genes expressed in brain of adult male zebra finches. Goal of ZEBrA project is to develop publicly available on-line digital atlas that documents expression of large collection of genes within brain of adult male zebra finches.
View all literature mentionsThis polyclonal secondary targets IgG (H+L)
View all literature mentionsA tool to design target-specific primers for polymerase chain reaction (PCR). It uses Primer3 to design PCR primers and then uses BLAST and global alignment algorithm to screen primers against user-selected database in order to avoid primer pairs (all combinations including forward-reverse primer pair, forward-forward as well as reverse-reverse pairs) that can cause non-specific amplifications.
View all literature mentionsWeb search tool to find regions of similarity between biological sequences. Program compares nucleotide or protein sequences to sequence databases and calculates statistical significance. Used for identifying homologous sequences.
View all literature mentionsDatabase of nucleotide sequences from several sources, including GenBank, RefSeq, TPA and PDB. Genome, gene and transcript sequence data provide the foundation for biomedical research and discovery.
View all literature mentionsThis polyclonal targets IgG
View all literature mentionsThis polyclonal targets Choline Acetyltransferase
View all literature mentionsThis monoclonal targets VGlut2
View all literature mentionsThis unknown targets
View all literature mentionsThis unknown targets Digoxigenin
View all literature mentions