RESUMO
Paraventricular thalamic nucleus (PVT) is an essential component of the midline thalamus, which has been regarded as a transmit relay nucleus and an integrated center in multiple behaviors including wakefulness, food intake, addiction, reward and fear memory. PVT is predominantly populated with glutaminergic excitatory neurons expressing vesicular glutamate transporter-2 (VGluT2) but without GABAergic inhibitory neurons. Therefore, based on the paradox of its multiplexed roles in different behaviors and its comparatively simplex excitatory nature, more specific subclassification of excitatory PVT neurons is required in studies in this field. In the present review, morphological and electrophysiological characteristics, efferent and afferent connections, and morphological and functional distinctions in anterior subregion and posterior subregion of PVT are summarized. In addition, neural connections and neurochemical properties are used as subclassification criteria in PVT neurons. This review might explain the integrated role of PVT in different behaviors, which would be helpful for further studies on the PVT.
RESUMO
Objective:To compare the difference in the onset time of the trunk muscles activity in individuals with and without nonspecific low back pain (NLBP) during upper limb flexion and abduction. Methods:From September to December, 2017, 21 patients with NLBP (NLBP group) and 21 volunteers (control group) participated in this study. Surface electromyography (sEMG) signals were recorded from the anterior deltoid, middle deltoid, multifidus and erector spinae muscles during upper limb flexion and abduction in standing position. Relative differences in the onset times between each muscle and the prime mover were calculated. Results:During upper limb flexion, the right multifidus muscle, bilateral erector spinae were activated in advance of the agonist muscle (anterior deltoid), while the left multifidus muscle was delayed relative to the agonist muscle in both groups. The onset time of the right erector spinae was significantly delayed in NLBP group than in the control group (t = -2.393, P = 0.019). During upper limb abduction, bilateral multifidus muscle and bilateral erector spinae were activated in advance of the agonist muscle (middle deltoid) in the control group. Additionally, in NLBP group, the left erector spinae was activated in advance of the agonist muscle, bilateral multifidus and right erector spinae were delayed relative to the agonist muscle. There was no significant difference in the relative onset time between both groups (t < 1.393, P > 0.05). Conclusion:During upper limb flexion and abduction, the trunk muscles of the lower back are activated in advance for healthy individuals, while individuals with NLBP have a possibly delayed activation of trunk muscles.
RESUMO
<p><b>OBJECTIVE</b>To examine the vesicular glutamate transporters (VGluTs: VGluT1-VGluT3) in the peripheral vestibular system.</p><p><b>METHODS</b>The vestibular structures, including Scarpa's ganglion (vestibular ganglion, VG), maculae of utricle and saccule, and ampullary cristae, from normal Sprague-Dawley rats were processed immunohistochemically for VGluTs, by avidin-biotinylated peroxidase complex method, with 3-3'-diaminobenzidine (DAB) as chromogen.</p><p><b>RESULTS</b>(1) VGluT1 was localized to partial neurons of VG and to the putative primary afferent fibers innervating vestibular end-organs. (2) Intense VGluT3 immunoreactivity was detected in large number of sensory epithelia cells, and weak labeling of VGluT3-positive afferent fibers was in the maculae and ampullary cristae. (3) No or very weak VGluT2 immunoreactivity was observed in the VG and acoustic maculae.</p><p><b>CONCLUSION</b>These results provide the morphological support that glutamate exists in the peripheral vestibular system, and it may play an important role in the centripetal vestibular transmission.</p>