GABAergic and pallidal terminals in the thalamic reticular nucleus of squirrel monkeys

1994 ◽  
Vol 101 (3) ◽  
Author(s):  
C. Asanuma
Keyword(s):  
Squirrel Monkeys ◽  
Thalamic Reticular Nucleus ◽  
Reticular Nucleus

Thalamic Reticular Nucleus in Caiman crocodilus: Immunohistochemical Staining

2018 ◽  
Vol 92 (3-4) ◽  
pp. 142-166 ◽  
Author(s):  
Michael B. Pritz
Keyword(s):  
Glutamic Acid ◽  
Glutamic Acid Decarboxylase ◽  
Immunohistochemical Staining ◽  
Medial Forebrain Bundle ◽  
Transverse Plane ◽  
Thalamic Reticular Nucleus ◽  
Reticular Nucleus ◽  
Acid Decarboxylase ◽  
Caiman Crocodilus ◽  
Monoclonal Mouse

The thalamic reticular nucleus in reptiles, Caiman crocodilus, shares a number of morphological similarities with its counterpart in mammals. In view of the immunohistochemical properties of this nucleus in mammals and the more recently identified complexity of this neuronal aggregate in Caiman, this nucleus was investigated using a number of antibodies. These results were compared with findings described for other amniotes. The following antibodies gave consistent and reproducible results: polyclonal sheep anti-parvalbumin (PV), monoclonal mouse anti-PV, and polyclonal sheep anti-glutamic acid decarboxylase (GAD). In the transverse plane, this nucleus is divided into two. In each part, a compact group of cells sits on top of the fibers of the forebrain bundle with scattered cells among these fibers. In the lateral forebrain bundle, this neuronal aggregate is represented by the dorsal peduncular nucleus and the perireticular nucleus while, in the medial forebrain bundle, these parts are the interstitial nucleus and the scattered cells in this fiber tract. The results of this study are the following. First, the thalamic reticular nucleus of Caiman contains GAD(+) and PV(+) neurons, which is similar to what has been described in other amniotes. Second, the morphology and distribution of many GAD(+) and PV(+) neurons in the dorsal peduncular and perireticular nuclei are similar and suggest that these neurons colocalize these markers. Third, neurons in the interstitial nucleus and in the medial forebrain bundle are GAD(+) and PV(+). At the caudal pole of the thalamic reticular nucleus, PV immunoreactive cells predominated and avoided the central portion of this nucleus where GAD(+) cells were preferentially located. However, GAD(+) cells were sparse when compared with PV(+) cells. This immunohistochemically different area in the caudal pole is considered to be an area separate from the thalamic reticular nucleus.

scholarly journals The therapeutic mechanism of epilepsy seizures in different target areas: Research on a theoretical model

2021 ◽  
Vol 29 ◽  
pp. 455-461
Author(s):  
Bing Hu ◽  
Zhizhi Wang ◽  
Minbo Xu ◽  
Luyao Zhu ◽  
Dingjiang Wang
Keyword(s):  
Pyramidal Neurons ◽  
Control Mechanism ◽  
Difficult Problem ◽  
Calculation Model ◽  
Thalamic Reticular Nucleus ◽  
Reticular Nucleus ◽  
Theoretical Support ◽  
Therapeutic Mechanism ◽  
Optimal Target ◽  
Selection Of

BACKGROUND: The selection of optimal target areas in the surgical treatment of epilepsy is always a difficult problem in medicine. OBJECTIVE: We employed a theoretical calculation model to explore the control mechanism of seizures by an external voltage stimulus acting in different nerve nuclei. METHODS: Theoretical analysis and numerical simulation were combined. RESULTS: The globus pallidus, excitatory pyramidal neurons, striatal D1 neurons, thalamic reticular nucleus and specific relay nuclei were selected, we analyzed that the electrical stimulation has different effects in these target areas. CONCLUSIONS: The data selected were reasonable in study, the results may give a theoretical support for similar studies in clinical.

scholarly journals Synaptic properties of the feedback connections from the thalamic reticular nucleus to the dorsal lateral geniculate nucleus

2020 ◽  
Vol 124 (2) ◽  
pp. 404-417 ◽  
Author(s):  
Peter W. Campbell ◽  
Gubbi Govindaiah ◽  
Sean P. Masterson ◽  
Martha E. Bickford ◽  
William Guido
Keyword(s):  
Lateral Geniculate Nucleus ◽  
Dorsal Lateral Geniculate Nucleus ◽  
Thalamic Reticular Nucleus ◽  
Reticular Nucleus ◽  
Lateral Geniculate ◽  
Dependent Form ◽  
Dorsal Lateral Geniculate ◽  
Feedback Connections ◽  
Spike Firing ◽  
Stimulation Of

The thalamic reticular nucleus (TRN) modulates thalamocortical transmission through inhibition. In mouse, TRN terminals in the dorsal lateral geniculate nucleus (dLGN) form synapses with relay neurons but not interneurons. Stimulation of TRN terminals in dLGN leads to a frequency-dependent form of inhibition, with higher rates of stimulation leading to a greater suppression of spike firing. Thus, TRN inhibition appears more dynamic than previously recognized, having a graded rather than an all-or-none impact on thalamocortical transmission.

scholarly journals Selective Loss and Selective Sparing of Neurons in the Thalamic Reticular Nucleus following Human Cardiac Arrest

1993 ◽  
Vol 13 (4) ◽  
pp. 558-567 ◽  
Author(s):  
Douglas T. Ross ◽  
David I. Graham
Keyword(s):  
Cardiac Arrest ◽  
Heart Surgery ◽  
Neuronal Damage ◽  
Open Heart Surgery ◽  
Thalamic Reticular Nucleus ◽  
Global Cerebral Ischemia ◽  
Reticular Nucleus ◽  
Thalamic Nuclei ◽  
Attentional Processing ◽  
Thalamic Relay Nuclei

Neurons in the portion of the human thalamic reticular nucleus (RT) associated with the prefrontal cortex and mediodorsal thalamic nuclei were found to be selectively vulnerable to ischemic neuronal damage following relatively short (≤5-min) duration cardiac arrest. In contrast, selective sparing of these RT neurons occurred in cases with longer (>10-min) duration of arrest that was sufficient to produce extensive ischemic neuronal damage throughout the cerebral cortex and thalamic relay nuclei. The selective degeneration of RT neurons appears to require the sustained activity of corticothalamic or thalamocortical projections to the RT following the ischemic insult. Loss of RT neurons associated with the frontal cortex and mediodorsal thalamus may be the biological basis of some types of persisting cognitive deficits in attentional processing experienced by patients following cardiac arrest, open heart surgery, or other forms of brief global cerebral ischemia.

Limbic seizures increase pronociceptin mRNA levels in the thalamic reticular nucleus

Neuroreport ◽  
1999 ◽  
Vol 10 (3) ◽  
pp. 541-546 ◽  
Author(s):  
Gianni Bregola ◽  
Sanzio Candeletti ◽  
Patrizia Romualdi ◽  
Michele Simonato
Keyword(s):  
Thalamic Reticular Nucleus ◽  
Reticular Nucleus ◽  
Mrna Levels ◽  
Limbic Seizures

High Responsiveness and Direction Sensitivity of Neurons in the Rat Thalamic Reticular Nucleus to Vibrissa Deflections

2000 ◽  
Vol 83 (5) ◽  
pp. 2791-2801 ◽  
Author(s):  
Jed A. Hartings ◽  
Simona Temereanca ◽  
Daniel J. Simons
Keyword(s):  
Sensory Information ◽  
Thalamic Reticular Nucleus ◽  
Reticular Nucleus ◽  
Directional Sensitivity ◽  
Starting Position ◽  
Baseline Activity ◽  
High Responsiveness ◽  
Direction Of Movement ◽  
Mystacial Vibrissae ◽  
Direction Sensitivity

The thalamic reticular nucleus (Rt) is strategically positioned to integrate descending and ascending signals in the control of sensorimotor and other thalamocortical activity. Its prominent role in the generation of sleep spindles notwithstanding, relatively little is known of Rt function in regulating interactions with the sensory environment. We recorded and compared the responses of individual Rt and thalamocortical neurons in the ventroposterior medial (VPm) nucleus of the rat to controlled deflections of mystacial vibrissae. Transient Rt responses to the onset (on) and offset (off) of vibrissa deflection are larger and longer in duration than those of VPm and of all other populations studied in the whisker/barrel pathway. Magnitudes of on and off responses in Rt were negatively correlated with immediately preceding activities, suggesting a contribution of low-threshold T-type Ca2+ channels. Rt neurons also respond with high tonic firing rates during sustained vibrissa deflections. By comparison, VPm neurons are less likely to respond tonically and are more likely to exhibit tonic suppression. Rt and VPm populations are similar to each other, however, in that they retain properties of directional sensitivity established in primary afferent neurons. In both populations neurons are selective for deflection angle and exhibit directional consistency, responding best to a particular direction of movement regardless of the starting position of the vibrissal hair. These findings suggest a role for Rt in the processing of detailed sensory information. Temporally, Rt may function to limit the duration of stimulus-evoked VPm responses and to focus them on rapid vibrissa perturbations. Moreover, by regulating the baseline activity of VPm neurons, Rt may indirectly enhance the response selectivity of layer IV barrel neurons to synchronous VPm firing.

scholarly journals Focal Stimulation of the Thalamic Reticular Nucleus Induces Focal Gamma Waves in Cortex

1998 ◽  
Vol 79 (1) ◽  
pp. 474-477 ◽  
Author(s):  
Kurt D. Macdonald ◽  
Eva Fifkova ◽  
Michael S. Jones ◽  
Daniel S. Barth
Keyword(s):  
Electrical Stimulation ◽  
Internal Capsule ◽  
Thalamic Reticular Nucleus ◽  
Gamma Activity ◽  
Reticular Nucleus ◽  
Cortical Arousal ◽  
Electrical Potentials ◽  
Gamma Frequency ◽  
Slow Potentials ◽  
Stimulation Of

MacDonald, Kurt D., Eva Fifkova, Michael S. Jones, and Daniel S. Barth. Focal stimulation of the thalamic reticular nucleus induces focal gamma waves in cortex. J. Neurophysiol. 79: 474–477, 1998. Electrical stimulation of the thalamic reticular nucleus (TRN; 0.5-s trains of 500-Hz 0.5-ms pulses at 5–10 μA) evokes focal oscillations of cortical electrical potentials in the gamma frequency band (∼35–55 Hz). These evoked oscillations are specific to either the somatosensory or auditory cortex and to subregions of the cortical receptotopic map, depending on what part of the TRN is stimulated. Focal stimulation of the internal capsule, however, evokes focal slow potentials, without gamma activity. Our results suggest that the TRN's role extends beyond that of general cortical arousal to include specific modality and submodality activation of the forebrain.

First order connections of the visual sector of the thalamic reticular nucleus in marmoset monkeys (Callithrix jacchus)

2007 ◽  
Vol 24 (6) ◽  
pp. 857-874 ◽  
Author(s):  
THOMAS FITZGIBBON ◽  
BRETT A. SZMAJDA ◽  
PAUL R. MARTIN
Keyword(s):  
Visual Field ◽  
Callithrix Jacchus ◽  
Higher Order ◽  
Dorsal Lateral Geniculate Nucleus ◽  
Thalamic Reticular Nucleus ◽  
Reticular Nucleus ◽  
Lower Visual Field ◽  
First Order ◽  
Cortical Areas ◽  
Visual Areas

The thalamic reticular nucleus (TRN) supplies an important inhibitory input to the dorsal thalamus. Previous studies in non-primate mammals have suggested that the visual sector of the TRN has a lateral division, which has connections with first-order (primary) sensory thalamic and cortical areas, and a medial division, which has connections with higher-order (association) thalamic and cortical areas. However, the question whether the primate TRN is segregated in the same manner is controversial. Here, we investigated the connections of the TRN in a New World primate, the marmoset (Callithrix jacchus). The topography of labeled cells and terminals was analyzed following iontophoretic injections of tracers into the primary visual cortex (V1) or the dorsal lateral geniculate nucleus (LGNd). The results show that rostroventral TRN, adjacent to the LGNd, is primarily connected with primary visual areas, while the most caudal parts of the TRN are associated with higher order visual thalamic areas. A small region of the TRN near the caudal pole of the LGNd (foveal representation) contains connections where first (lateral TRN) and higher order visual areas (medial TRN) overlap. Reciprocal connections between LGNd and TRN are topographically organized, so that a series of rostrocaudal injections within the LGNd labeled cells and terminals in the TRN in a pattern shaped like rostrocaudal overlapping “fish scales.” We propose that the dorsal areas of the TRN, adjacent to the top of the LGNd, represent the lower visual field (connected with medial LGNd), and the more ventral parts of the TRN contain a map representing the upper visual field (connected with lateral LGNd).

Mapping of the Functional Interconnections Between Thalamic Reticular Neurons Using Photostimulation

2006 ◽  
Vol 96 (5) ◽  
pp. 2593-2600 ◽  
Author(s):  
Ying-Wan Lam ◽  
Christopher S. Nelson ◽  
S. Murray Sherman
Keyword(s):  
Laser Scanning ◽  
Spatial Extent ◽  
Thalamic Reticular Nucleus ◽  
Reticular Nucleus ◽  
Reticular Cell ◽  
Relay Cell ◽  
Dominant Form ◽  
Electrical Synapses ◽  
Reticular Neurons ◽  
Reticular Cells

The thalamic reticular nucleus is strategically located in the axonal pathways between thalamus and cortex, and reticular cells exert strong, topographic inhibition on thalamic relay cells. Although evidence exists that reticular neurons are interconnected through conventional and electrical synapses, the spatial extent and relative strength of these synapses are unclear. To address these issues, we used uncaging of glutamate by laser-scanning photostimulation to provide precisely localized and consistent activation of reticular cell bodies and dendrites in an in vitro slice preparation from the rat as a means to study reticulo-reticular connections. Among the 47 recorded reticular neurons, 29 (62%) received GABAergic axodendritic input from an area immediately surrounding each of the recorded cell bodies, and 8 (17%) responded with depolarizing spikelets, suggesting inputs through electrical synapses. We also found that TTX completely blocked all evoked IPSCs, implying that any dendrodendritic synapses between reticular cells either are relatively weak, have no nearby glutamatergic receptors, or are dependent on back-propagation of action potentials. Finally, we showed that the GABAergic connections between reticular cells are weaker than those from reticular cells to relay cells. Our results suggest that the GABAergic axodendritic synapse is the dominant form of reticulo-reticular connectivity, and because they are much weaker than the reticulo-relay cell synapses, their functional purpose may be to regulate the spatial extent of the reticular inhibition on relay cells.

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