Centre Median Nucleus Of Thalamus


Aim of this study was to investigate whether Deep Brain Stimulation (DBS) of the centre median nucleus/Parafascicular (CM/PF) Complex is useful in reducing extrapyramidal symptoms in advanced Parkinson's Disease (PD) patients.  

Neuronal loss occurred from mediodorsal parvocellularis, rostral center medial, central lateral and paracentral nuclei in moderately disabled patients; and from mediodorsal magnocellularis, caudal center medial, rhomboid, and parafascicular nuclei in severely disabled patients; and all of the above and the centre median nucleus in vegetative patients.  

Surprisingly, area 3a receives the majority of its input from thalamic nuclei associated with the motor system, posterior division of the ventral lateral nucleus of the thalamus (VL), the mediodorsal nucleus (MD), and intralaminar nuclei including the central lateral nucleus (CL) and the centre median nucleus (CM).  

By contrast, the posterior group of intralaminar nuclei (centre median nucleus and parafascicular nucleus) showed a complementary pattern of staining; the centre median nucleus showed immunoreactivity only for one calcium-binding protein, parvalbumin, while the parafascicular nucleus showed immunoreactivity for both calbindin-D28k and calretinin.  

Predominant PV immunostaining characterizes primary somatosensory, visual and auditory nuclei, the ventral lateral posterior nucleus, reticular nucleus (R), and to a lesser degree also, lateral part of the centre median nucleus, and anterior, lateral, and inferior divisions of the pulvinar complex.  

The excitotoxin ibotenic acid was injected bilaterally into the intralaminar centre median nucleus of chronically implanted cats in order to study the effects of early excitation of centre median population on electrographic correlates of behavioral states and to compare them to those induced by injection into intralaminar centralis lateralis nucleus, previously shown.  

In the latter species, GABA- or GAD-immunopositive perikarya were distributed throughout the anterior intralaminar nuclei, whereas in the posterior intralaminar complex they prevailed in the lateral part of the centre median nucleus and around the fasciculus retroflexus.  

This finding together with the observation that after DL-AG the visual evoked potentials increased in the primary visual cortex and decreased in the centre median nucleus and in the reticular formation support the view about the role of the cortex in the increased brain excitability and in the increased photosensitivity after allylglycine.  

Studies were made on the effect of the neuroexcitatory agent kainic acid, microinjected into raphe dorsal nucleus by glass micropipette and an air pressure system in doses ranging from 0.2 to 24.0 nmol (in volumes from 0.05 microliter to 0.47 microliter), on the somatosensory evoked potentials and their cycles of recovery (excitability) obtained from cortex (primary somatosensory and parietal associative), thalamus (ventral posterolateral nucleus and centre median nucleus), mesencephalic reticular formation and raphe dorsal nucleus.  

Triply labeled neurons were scattered throughout the TIN until the rostral part of the centre median nucleus.  

Stimulation of parietal cortex resulted in habituation that occurred significantly slower than habituation to auditory cortex stimulation, and significantly faster than habituation to stimulation of the midbrain reticular formation or the centre median nucleus of the thalamus.  

Cats were tested for the effect of unilateral cooling of the centre median nucleus of the thalamus (CM) or of the caudate nucleus (Cd) as they performed a simple reaction time schedule.  

The posteromedian choroideal and thalamic system, in its infrathalamic portion, gives off lateral mesencephalosubthalamic, inferocentral (for the tips of the arcuate nucleus and the inferolateral part of the centre median nucleus), brachiopulvinarian and posterocentral arteries.  

The electrical activity at the centre median nucleus of the thalamus (CEM), which responded to noxious stimuli and was inhibited by nitrous oxide inhalation, was recorded as an indicator of the degree of pain sensation.  


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