Glutamate-like immunoreactivity in neurons of the laterodorsal tegmental and pedunculopontine nuclei in the rat

doi:10.1016/0304-3940(90)90170-E

Neuroscience Letters

Volume 120, Issue 1, 27 November 1990, Pages 70-73

https://doi.org/10.1016/0304-3940(90)90170-E Get rights and content

Abstract

Studies of the pedunculopontine (PPT) and laterodorsal tegmental (LDT) nuclei in the mesopontine tegmentum have emphasized the organization and projections of the cholinergic neurons. We report here that exhibiting glutamate immunoreactivity are present in both the LDT and PPT. These glutamatergic neurons are interspersed among the cholinergic neurons within both nuclei with no apparent segregation. These data raise the possibility that excitatory amino acids contribute to the functions of the LDT and PPT.

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Citation Excerpt :
Glutamatergic neurons, which express type 2 vesicular glutamate transporter (VGlut2), have a smaller somata (<20 μm) with 2 to 4 primary dendrites (Clements and Grant, 1990; Ichinohe et al., 2000; Jia et al., 2003; Wang and Morales, 2009). GABAergic neurons, which express the 67 KD isoform of glutamate decarboxylase (GAD67), are similar in size to glutamatergic neurons (Clements and Grant, 1990; Ichinohe et al., 2000; Jia et al., 2003; Wang and Morales, 2009). Despite its original classification as a cholinergic nucleus, cholinergic neurons constitute only 25–30% of the total number of neurons in the PPN.
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Glutamate-like immunoreactivity in neurons of the laterodorsal tegmental and pedunculopontine nuclei in the rat

Abstract

Cholinergic projection to the rat substantia nigra from the pedunculopontine tegmental nucleus

Brain Res.

Innervation of substantia nigra neurons by cholinergic afferents from pedunculopontine nucleus in the rat: neuroanatomical and electrophysiological evidence

Neuroscience

Glutamate and acetylcholine are colocalized in the laterodorsal tegmental and pedunculopontine nuclei

Soc. Neurosci. Abstr.

Behavioral investigation of the coexistence of substance P, corticotropin releasing factor, and acetylcholinesterase in lateral dorsal tegmental neurons projecting to the medial frontal cortex of the rat

Peptides

GABAergic basal forebrain neurons project to the neocortex: the localization of glutamic acid decarboxylase and choline acetyltransferase in feline corticipetal neurons

J. Comp. Neurol.

Locomotion inducing sites in the vicinity of the pedunculopontine nucleus

Brain Res. Bull.

Separate non-cholinergic descending projections and cholinergic ascending projections from the nucleus tegmenti pedunculopontinus

Brain Res.

Cholinergic projections to the substantia nigra from the pedunculopontine and lateral dorsal tegmental nuclei

Neuroscience

Use of avidin biotin peroxidase complex in immunoperoxidase techniques

J. Histochem. Cytochem.

The effects of brainstem peribrachial stimulation on neurons of the lateral geniculate nucleus

Neuroscience

Cholinergic neurons containing GABA-like and/or glutamic acid decarboxylase-like immunoreactivities in various brain regions of the rat

Exp. Brain Res.

Cholinergic vs. noncholinergic efferents from the mesopontine tegmentum to the extrapyramidal motor system nuclei

J. Comp. Neurol.

In vitro study of pedunculopontine neurons and ACh actions