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Pulvinar projections to the striatum and amygdala in the tree shrew.

Day-Brown JD, Wei H, Chomsung RD, Petry HM, Bickford ME - Front Neuroanat (2010)

Bottom Line: Both capabilities are thought to be mediated by pathways from the retina through the superior colliculus (SC) and pulvinar nucleus.Using immunocytochemical staining for substance P (SP) and parvalbumin (PV) to reveal the patch/matrix organization of tree shrew striatum, we found that SP-rich/PV-poor patches interlock with a PV-rich/SP-poor matrix.Electron microscopy revealed that the postsynaptic targets of tracer-labeled pulvino-striatal and pulvino-amygdala terminals are spines, demonstrating that the pulvinar nucleus projects to the spiny output cells of the striatum matrix and the lateral amygdala, potentially relaying: (1) topographic visual information from SC to striatum to aid in guiding precise movements, and (2) non-topographic visual information from SC to the amygdala alerting the animal to potentially dangerous visual images.

View Article: PubMed Central - PubMed

Affiliation: Department of Anatomical Sciences and Neurobiology, University of Louisville Medical Center Louisville, KY, USA.

ABSTRACT
Visually guided movement is possible in the absence of conscious visual perception, a phenomenon referred to as "blindsight." Similarly, fearful images can elicit emotional responses in the absence of their conscious perception. Both capabilities are thought to be mediated by pathways from the retina through the superior colliculus (SC) and pulvinar nucleus. To define potential pathways that underlie behavioral responses to unperceived visual stimuli, we examined the projections from the pulvinar nucleus to the striatum and amygdala in the tree shrew (Tupaia belangeri), a species considered to be a prototypical primate. The tree shrew brain has a large pulvinar nucleus that contains two SC-recipient subdivisions; the dorsal (Pd) and central (Pc) pulvinar both receive topographic ("specific") projections from SC, and Pd receives an additional non-topographic ("diffuse") projection from SC (Chomsung et al., 2008). Anterograde and retrograde tract tracing revealed that both Pd and Pc project to the caudate and putamen, and Pd, but not Pc, additionally projects to the lateral amygdala. Using immunocytochemical staining for substance P (SP) and parvalbumin (PV) to reveal the patch/matrix organization of tree shrew striatum, we found that SP-rich/PV-poor patches interlock with a PV-rich/SP-poor matrix. Confocal microscopy revealed that tracer-labeled pulvino-striatal terminals preferentially innervate the matrix. Electron microscopy revealed that the postsynaptic targets of tracer-labeled pulvino-striatal and pulvino-amygdala terminals are spines, demonstrating that the pulvinar nucleus projects to the spiny output cells of the striatum matrix and the lateral amygdala, potentially relaying: (1) topographic visual information from SC to striatum to aid in guiding precise movements, and (2) non-topographic visual information from SC to the amygdala alerting the animal to potentially dangerous visual images.

No MeSH data available.


Related in: MedlinePlus

Pulvino-striatal and pulvino-amygdala terminals contact spines. Terminals labeled by the anterograde transport of BDA injected in the pulvinar nucleus contact (white arrows) spines in the putamen (A–C) and the amygdala (D–G). Single (A,B,D,F,G) perforated (C) and multiple (E) contacts were observed. Postembedding immunocytochemical staining for GABA revealed surrounding GABAergic terminals (high density of gold particles; + denotes) but BDA-labeled terminals and postsynaptic spines contained a low density of gold particles. Scale bar = 0.5 μm and applies to all panels.
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Figure 5: Pulvino-striatal and pulvino-amygdala terminals contact spines. Terminals labeled by the anterograde transport of BDA injected in the pulvinar nucleus contact (white arrows) spines in the putamen (A–C) and the amygdala (D–G). Single (A,B,D,F,G) perforated (C) and multiple (E) contacts were observed. Postembedding immunocytochemical staining for GABA revealed surrounding GABAergic terminals (high density of gold particles; + denotes) but BDA-labeled terminals and postsynaptic spines contained a low density of gold particles. Scale bar = 0.5 μm and applies to all panels.

Mentions: Using electron microscopy, we examined a total of 181 pulvino-putamen terminals (labeled by the anterograde transport of BDA injected into the Pd and/or Pc) that were involved in synaptic contacts. No size differences were detected in the populations of terminals labeled by Pd, Pc, or combined Pd/Pc injections (Pd injections: 0.48 ± 0.30 μm2, Pc injections: 0.47 ± 0.24 μm2, Pd/Pc injections: 0.47 ± 0.27 μm2). Most terminals formed single synapses (62%, Figures 5A,B), but smaller numbers of perforated (34%, Figure 5C) or multiple (4%) synaptic contacts were also identified. Pulvino-putamen terminals primarily contacted spines (Pc, 100%; Pd, 94%; Pd/Pc, 93.3%) as illustrated in Figures 5A–C. This suggests that pulvino-striatal terminals contact GABAergic spiny projection neurons. We attempted to confirm the GABAergic nature of the postsynaptic targets by using postembedding immunocytochemical techniques to reveal the presence of GABA. However, we did not observe any accumulation of GABA within spines, although GABAergic terminals were easily detected by a qualitative assessment of gold particle density (Figures 5A and G).


Pulvinar projections to the striatum and amygdala in the tree shrew.

Day-Brown JD, Wei H, Chomsung RD, Petry HM, Bickford ME - Front Neuroanat (2010)

Pulvino-striatal and pulvino-amygdala terminals contact spines. Terminals labeled by the anterograde transport of BDA injected in the pulvinar nucleus contact (white arrows) spines in the putamen (A–C) and the amygdala (D–G). Single (A,B,D,F,G) perforated (C) and multiple (E) contacts were observed. Postembedding immunocytochemical staining for GABA revealed surrounding GABAergic terminals (high density of gold particles; + denotes) but BDA-labeled terminals and postsynaptic spines contained a low density of gold particles. Scale bar = 0.5 μm and applies to all panels.
© Copyright Policy - open-access
Related In: Results  -  Collection

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Show All Figures
getmorefigures.php?uid=PMC2991220&req=5

Figure 5: Pulvino-striatal and pulvino-amygdala terminals contact spines. Terminals labeled by the anterograde transport of BDA injected in the pulvinar nucleus contact (white arrows) spines in the putamen (A–C) and the amygdala (D–G). Single (A,B,D,F,G) perforated (C) and multiple (E) contacts were observed. Postembedding immunocytochemical staining for GABA revealed surrounding GABAergic terminals (high density of gold particles; + denotes) but BDA-labeled terminals and postsynaptic spines contained a low density of gold particles. Scale bar = 0.5 μm and applies to all panels.
Mentions: Using electron microscopy, we examined a total of 181 pulvino-putamen terminals (labeled by the anterograde transport of BDA injected into the Pd and/or Pc) that were involved in synaptic contacts. No size differences were detected in the populations of terminals labeled by Pd, Pc, or combined Pd/Pc injections (Pd injections: 0.48 ± 0.30 μm2, Pc injections: 0.47 ± 0.24 μm2, Pd/Pc injections: 0.47 ± 0.27 μm2). Most terminals formed single synapses (62%, Figures 5A,B), but smaller numbers of perforated (34%, Figure 5C) or multiple (4%) synaptic contacts were also identified. Pulvino-putamen terminals primarily contacted spines (Pc, 100%; Pd, 94%; Pd/Pc, 93.3%) as illustrated in Figures 5A–C. This suggests that pulvino-striatal terminals contact GABAergic spiny projection neurons. We attempted to confirm the GABAergic nature of the postsynaptic targets by using postembedding immunocytochemical techniques to reveal the presence of GABA. However, we did not observe any accumulation of GABA within spines, although GABAergic terminals were easily detected by a qualitative assessment of gold particle density (Figures 5A and G).

Bottom Line: Both capabilities are thought to be mediated by pathways from the retina through the superior colliculus (SC) and pulvinar nucleus.Using immunocytochemical staining for substance P (SP) and parvalbumin (PV) to reveal the patch/matrix organization of tree shrew striatum, we found that SP-rich/PV-poor patches interlock with a PV-rich/SP-poor matrix.Electron microscopy revealed that the postsynaptic targets of tracer-labeled pulvino-striatal and pulvino-amygdala terminals are spines, demonstrating that the pulvinar nucleus projects to the spiny output cells of the striatum matrix and the lateral amygdala, potentially relaying: (1) topographic visual information from SC to striatum to aid in guiding precise movements, and (2) non-topographic visual information from SC to the amygdala alerting the animal to potentially dangerous visual images.

View Article: PubMed Central - PubMed

Affiliation: Department of Anatomical Sciences and Neurobiology, University of Louisville Medical Center Louisville, KY, USA.

ABSTRACT
Visually guided movement is possible in the absence of conscious visual perception, a phenomenon referred to as "blindsight." Similarly, fearful images can elicit emotional responses in the absence of their conscious perception. Both capabilities are thought to be mediated by pathways from the retina through the superior colliculus (SC) and pulvinar nucleus. To define potential pathways that underlie behavioral responses to unperceived visual stimuli, we examined the projections from the pulvinar nucleus to the striatum and amygdala in the tree shrew (Tupaia belangeri), a species considered to be a prototypical primate. The tree shrew brain has a large pulvinar nucleus that contains two SC-recipient subdivisions; the dorsal (Pd) and central (Pc) pulvinar both receive topographic ("specific") projections from SC, and Pd receives an additional non-topographic ("diffuse") projection from SC (Chomsung et al., 2008). Anterograde and retrograde tract tracing revealed that both Pd and Pc project to the caudate and putamen, and Pd, but not Pc, additionally projects to the lateral amygdala. Using immunocytochemical staining for substance P (SP) and parvalbumin (PV) to reveal the patch/matrix organization of tree shrew striatum, we found that SP-rich/PV-poor patches interlock with a PV-rich/SP-poor matrix. Confocal microscopy revealed that tracer-labeled pulvino-striatal terminals preferentially innervate the matrix. Electron microscopy revealed that the postsynaptic targets of tracer-labeled pulvino-striatal and pulvino-amygdala terminals are spines, demonstrating that the pulvinar nucleus projects to the spiny output cells of the striatum matrix and the lateral amygdala, potentially relaying: (1) topographic visual information from SC to striatum to aid in guiding precise movements, and (2) non-topographic visual information from SC to the amygdala alerting the animal to potentially dangerous visual images.

No MeSH data available.


Related in: MedlinePlus