Projection neurons of the basolateral amygdala: A correlative Golgi and retrograde tract tracing study

doi:10.1016/0361-9230(92)90177-Y

Brain Research Bulletin

Volume 28, Issue 2, February 1992, Pages 179-185

https://doi.org/10.1016/0361-9230(92)90177-Y Get rights and content

Abstract

This study analyzed the projection neurons of the anterior subdivision of the rat basolateral amygdaloid nucleus (BLa) by correlating the morphology of Golgi-stained neurons with the morphology of neurons that were retrogradely labeled by injections into the main terminal fields of BLa. In each animal multiple injections of horseradish peroxidase (HRP) and wheat germ agglutinin-conjugated HRP were made into the prefrontal cortex and rostral striatum. These injections labeled approximately 85% of BLa neurons. The great majority of labeled neurons were the same shape and relative size as the pyramidal (class I) neurons described in previous Golgi studies. The unlabeled neurons appeared to correspond to the nonpyramidal (class II and class III) neurons described in Golgi studies. Thus this investigation provides experimental evidence that the pyramidal neurons are the main projection neurons of BL, whereas most of the nonpyramidal cells are local circuit neurons.

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Citation Excerpt :
Our data also highlight similarities between CaMKIIα and GAD1 cells in NCM and subclasses of excitatory and inhibitory cell types in mammalian pallium. CaMKIIα neurons were largely non-pyramidal in morphology, contrary to the signature output neuron morphology in mammalian neocortex and the pallial amygdala,42 and previous work has not identified projections from NCM that exit pallium (though see Wild122). NCM instead makes reciprocal connections with other pallial domains, including the mesopallium, a large territory with neurons that recent developmental and genetic data demonstrate to have similar molecular markers to mammalian intra-telencephalic (IT) cells.13,58
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Citation Excerpt :
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Projection neurons of the basolateral amygdala: A correlative Golgi and retrograde tract tracing study

Abstract

Neurosci. Lett.

Brain Res. Bull.

Brain Res.

Neuroscience

Brain Res.

Immunocytochemical localization of glutamate decarboxylase in the rat basolateral amygdaloid nucleus, with special reference to GABAergic innervation of amygdalostriatal projection neurons

J. Comp. Neurol.

Amygdala

A note on the transneuronal transport of wheat germ agglutinin-conjugated horseradish peroxidase in the avian and rodent visual systems

Exp. Brain Res.

The amygdala of the cat: a Golgi study

Z. Zellforsch.

Laminar distribution of cortical efferent cells

Golgi studies on the amygdaloid nuclei of the cat

J. Hirnforsch.

A description of the amygdaloid complex in the rat and cat with observations on intra-amygdaloid axonal connections

J. Comp. Neurol.