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Pallidus Neurons (pallidu + neuron)

Distribution by Scientific Domains
Life Sciences75%

Kinds of Pallidus Neurons

  • globu pallidu neuron
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    Selected Abstracts

    Substance P excites globus pallidus neurons in vivo

    EUROPEAN JOURNAL OF NEUROSCIENCE, Issue 7 2007
    Qiao-Ling Cui
    Abstract Substance P is a member of the neurokinin family. Previous studies have reported the existence of substance P and its high-affinity receptor, neurokinin-1 receptor, in globus pallidus. Employing in vivo extracellular recording combined with behavioural tests, the effects of substance P in globus pallidus of rats were studied. Micropressure ejection of the selective neurokinin-1 receptor agonist [Sar9,Met(O2)11] substance P increased the spontaneous firing rate of pallidal neurons in a concentration-dependent manner, with increases of 27.3% at 0.01, 33.4% at 0.03, 45.5% at 0.1, 38.4% at 0.3 and 36.4% at 1.0 mm. The selective neurokinin-1 receptor antagonist SR140333B prevented the excitatory effects induced by [Sar9,Met(O2)11] substance P. In behaving rats, we observed the postural effects of neurokinin-1 receptor activation in the globus pallidus. Consistent with electrophysiological results, unilateral microinjection of [Sar9,Met(O2)11] substance P (0.1 mm) led to a SR140333B-sensitive contralateral deflection in the presence of systemic haloperidol administration. Combining electrophysiological and behavioural findings, we concluded that substance P produces excitatory effects on globus pallidus neurons via neurokinin-1 receptors. [source]

    Behavioral and electrophysiological effects of 5-HT in globus pallidus of 6-hydroxydopamine lesioned rats

    JOURNAL OF NEUROSCIENCE RESEARCH, Issue 7 2010
    Shu-Jing Zhang
    Abstract Anatomical studies have shown that the globus pallidus receives abundant 5-hydroxytryptamine (5-HT) innervations from raphe nuclei. 5-HT may occupy an important position in the modulation of motor function through its affect on the activity of globus pallidus. In the present study, intrapallidal microinjection of 5-HT (0.1 mM) alone did not induce any motor behavior or postural asymmetry in the unilateral 6-hydroxydopamine (6-OHDA)-lesioned rats. However, when infused concomitantly with a low dose of 3, 4-dihydroxyphenylalanine (L-DOPA, 3 mg/kg i.p.), which itself can induce modest contralateral rotational behavior, 5-HT significantly potentiated the number of contralateral rotations. To elucidate the cellular mechanism, in vivo extracellular recordings were performed to examine the effects of 5-HT on globus pallidus neurons. In normal rats, the predominant effect of micropressure ejection of 5-HT on pallidal neurons was excitation. In 6-OHDA-lesioned rats, although 5-HT increased the firing rate in most pallidal neurons, 5-HT-induced inhibitory effects was stronger than that on the unlesioned side as well as normal rats. Furthermore, 5-HT1B receptors are mainly involved in 5-HT-induced excitation while 5-HT1A receptors are involved in 5-HT-induced inhibition. The results suggest that 5-HT may potentiate the antiparkinsonian effect of L-DOPA through modulating the activity of globus pallidus. © 2009 Wiley-Liss, Inc. [source]

    Stereospecific activity of two glutamate analogs

    CHIRALITY, Issue 9 2004
    Juan Manuel Araujo Alvarez
    Abstract Two glutamic acid analogs, (+)-(S)- and (,)-(R)-4-(2,2-diphenyl-1,3,2-oxazaborolidin-5-oxo)propionic acid ((+)-(S)- and (,)-(R)-Trujillon, respectively), were prepared. The stereospecific activity of their pharmacological properties was studied. The median convulsant dose (CD50) and median lethal dose (LD50) were analyzed in female Swiss Webster mice and their effects in vivo on unitary electrical activity in globus pallidus neurons were elucidated in male Wistar rats. Compounds were characterized by 1H, 13C, and 11B nuclear magnetic resonance. The LD50 of (+)-(S)-Trujillon was 449.08 mg/kg and it increased spontaneous motor activity, while with (,)-(R)-Trujillon there was no mortality up to 1,000 mg/kg and it decreased spontaneous motor activity. The CD50 in experiments with (+)-(S)-Trujillon was 199.34 mg/kg. Unitary recording in globus pallidus neurons showed i.v. administration (+)-(S)-Trujillon (50 mg/kg) increased frequency 79.0 ± 23.0% in relation to basal response. (,)-(R)-Trujillon and (+)-(S)-glutamate (50 mg/kg each) did not provoke changes in spontaneous basal firing. Local infusion of (+)-(S)-Trujillon (1 nMol) increased spontaneous firing in most neurons tested by 269.0 ± 83.0% in relation to basal values. Intrapallidal infusion of (,)-(R)-Trujillon (1 nMol) and saline solution did not cause statistically significant changes in globus pallidus spiking. Results showed that (+)-(S)-Trujillon crosses the blood,brain barrier and has stereospecific activity. Chirality 16:586,591, 2004. © 2004 Wiley-Liss, Inc. [source]