Projections of the medial and lateral prefrontal cortices to the amygdala: a Phaseolus vulgaris leucoagglutinin study in the rat

doi:10.1016/0306-4522(95)00417-3

Neuroscience

Volume 71, Issue 1, March 1996, Pages 55-75

https://doi.org/10.1016/0306-4522(95)00417-3 Get rights and content

Abstract

The projections of different subfields of the medial and lateral prefrontal cortices to the amygdala were studied in the rat using the sensitive Phaseolus vulgaris leucoagglutinin anterograde tract tracing technique. Injections into the infralimbic cortex produced anterograde labeling in the lateral capsular subdivision of the central nucleus, superfacial (corticomedial) amygdaloid nuclei, lateral and accessory basal nuclei, and the anterior amygdaloid area. Injections into the caudal portion of the infralimbic cortex produced additional labeling in the intermediate subdivision of the central nucleus. The prelimbic cortex had projections to the medial portion of the magnocellular basal nucleus and adjacent portions of the lateral nucleus and lateral capsular subdivision of the central nucleus. The medial precentral cortex had projections to the rostromedial part of the magnocellular basal nucleus and adjacent portions of the lateral capsular subdivision of the central nucleus. Injections into the lateral orbital and ventral agranular insular cortices produced labeled fibers in the rostral part of the superficial amygdala, lateral capsular subdivision of the central nucleus, and the lateral and accessory basal nuclei. The dorsal agranular insular area had projections to several different subdivisions of the central nucleus as well as to the rostrolateral magnocellular basal nucleus; the latter projections were complementary to those originating in the prelimbic area.

The present study indicates that each portion of the prefrontal cortex has a distinctive projection to the amygdala. The ventral areas of the lateral and medial prefrontal cortices, which receive olfactory projections, are the only prefrontal cortical areas with projections to the olfactory-related superficial amygdaloid nuclei. The more dorsally situated prefrontal areas, the dorsal agranular insular area and prelimbic cortex, have complementary projections to the basal nucleus, suggesting that they modulate separate prefrontal cortico-striatal-pallidal circuits. The specificity of prefrontal cortico-amygdaloid projections is indicative of their involvement in discrete functions.

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Projections of the medial and lateral prefrontal cortices to the amygdala: a Phaseolus vulgaris leucoagglutinin study in the rat

Abstract

Neuroscience

Pharmac. Biochem. Behav.

Expl Neurol.

Brain Res.

Brain Res.

Neuroscience

Brain Res. Rev.

Neurosci. Lett.

Brain Res.

Neuroscience

Neurosci. Lett.

Neuroscience

Neuroscience

Neuroscience

Brain Res. Rev.

Behav. Brain Res.

Neuroscience Lett.

Neuroscience

Neuroscience

Behav. neural Biol.

Behav. Brain Res.

Physiol. Behav.

Brain Res. Bull.

Brain Res.

Brain Res.

Brain Res.

Basal ganglia-thalamocortical circuits: parallel substrates for motor, oculomotor, “prefrontal” and “limbic” functions

Prog. Brain Res.

An autoradiographic examination of corticocortical and subcortical projections of the mediodorsal projection (prefrontal) cortex in the rat

J. comp. Neurol.

The organization of the efferent projections from the pontine parabrachial area to the amygdaloid complex: a Phaseolus vulgaris leucoagglutinin (PHA-L) study in the rat

J. comp. Neurol.

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J. Neurophysiol.

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Acta neurol. scand.

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J. comp. Neurol.

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J. comp. Neurol.

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Amygdala

Amygdala and the memory of reward

Interaction of the amygdala with the frontal lobe in reward memory

Eur. J. Neurosci.

An anterograde neuroanatomical tracing method that shows the detailed morphology of neurons, their axons and terminals: immunohistochemical localization of an axonally transported plant lectin, Phaseolus vulgaris leucoagglutinin (PHA-L) tract tracing and immunohistochemistry

Brain Res.

Temporal lobe epilepsy: its possible contribution to the understanding of the functional significance of the amygdala and of its interaction with neocortical-temporal mechanisms

Neuropeptide neuronal efferents from the bed nucleus of the stria terminalis and central amygdaloid nucleus to the dorsal vagal complex in the rat

J. comp. Neurol.