Differential Effect of Functional Ablation of Thalamic Reticular Nucleus on the Acquisition of Passive and Active Avoidance

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.

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

Technology and Health Care ◽

10.3233/thc-218043 ◽

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.

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

Journal of Neurophysiology ◽

10.1152/jn.00757.2019 ◽

2020 ◽

Vol 124 (2) ◽

pp. 404-417 ◽

Cited By ~ 1

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.

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

Journal of Cerebral Blood Flow & Metabolism ◽

10.1038/jcbfm.1993.73 ◽

1993 ◽

Vol 13 (4) ◽

pp. 558-567 ◽

Cited By ~ 37

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.

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Limbic seizures increase pronociceptin mRNA levels in the thalamic reticular nucleus

Neuroreport ◽

10.1097/00001756-199902250-00018 ◽

1999 ◽

Vol 10 (3) ◽

pp. 541-546 ◽

Cited By ~ 12

Author(s):

Gianni Bregola ◽

Sanzio Candeletti ◽

Patrizia Romualdi ◽

Michele Simonato

Keyword(s):

Thalamic Reticular Nucleus ◽

Reticular Nucleus ◽

Mrna Levels ◽

Limbic Seizures

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

Experimental Brain Research ◽

10.1007/bf00227337 ◽

1994 ◽

Vol 101 (3) ◽

Cited By ~ 37

Author(s):

C. Asanuma

Keyword(s):

Squirrel Monkeys ◽

Thalamic Reticular Nucleus ◽

Reticular Nucleus

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

Journal of Neurophysiology ◽

10.1152/jn.2000.83.5.2791 ◽

2000 ◽

Vol 83 (5) ◽

pp. 2791-2801 ◽

Cited By ~ 31

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.

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

Journal of Neurophysiology ◽

10.1152/jn.1998.79.1.474 ◽

1998 ◽

Vol 79 (1) ◽

pp. 474-477 ◽

Cited By ~ 44

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.

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