No abstract available.
Neostriatum*

No abstract available.
Animals ; Neostriatum* ; Rats* ; Synapses*

Autapses selectively form in specific cell types in many brain regions. Previous studies have also found putative autapses in principal spiny projection neurons (SPNs) in the striatum. However, it remains unclear whether these neurons indeed form physiologically functional autapses. We applied whole-cell recording in striatal slices and identified autaptic cells by the occurrence of prolonged asynchronous release (AR) of neurotransmitters after bursts of high-frequency action potentials (APs). Surprisingly, we found no autaptic AR in SPNs, even in the presence of Sr²⁺. However, robust autaptic AR was recorded in parvalbumin (PV)-expressing neurons. The autaptic responses were mediated by GABA_A receptors and their strength was dependent on AP frequency and number. Further computer simulations suggest that autapses regulate spiking activity in PV cells by providing self-inhibition and thus shape network oscillations. Together, our results indicate that PV neurons, but not SPNs, form functional autapses, which may play important roles in striatal functions.
Parvalbumins/metabolism* ; Corpus Striatum/metabolism* ; Interneurons/physiology* ; Neurons/metabolism* ; Neostriatum

OBJECTIVETo observe the apoptosis of neural stem cells (NSCs) at differential time points after the dissociation of neurospheres by Accutase or trypsin.

METHODSThe NSCs were isolated from striatum of human fetals that suffered abortion at 12-16 weeks of pregnancy. The 3(rd)-5(th) passages of NSCs were digested by Accutase or trypsin. Only vortexing was applied, and the triturating by Pasteur pipette was avoided to attenuate the injury to the cells during the dissociation. The single cells were then stained by Annexin V/propidium iodide and Hoechst 33342. The apoptosis rates 2 and 24 hours after passaging were evaluated.

RESULTSThe trypan blue staining confirmed that immediately after the dissociation,the viability of cells digested by trypsin was (83.10 ± 6.76)%, which was significantly lower than that digested by Accutase,which was (91.65 ± 4.43)% (P<0.05). The apoptosis of the NSCs digested by Accutase was higher than that digested by trypsin at both 2 and 24 hours after passaging (P<0.01). Four days after the passaging, both the new clone formation rate and diameter of new spheres after trypsin digestion were significantly higher than those after Accutase digestion (P<0.01).

CONCLUSIONSAlthough the viability of NSCs immediately after the disassociation by trypsin is lower than that digested by Accutase, the apoptosis of NSCs subsequently caused by trypsin is lower than that caused by Accutase. Trypan blue test immediately after the disassociation can not be used as an indicator in estimating the apoptosis of NSCs during the expanding.

Apoptosis ; Collagenases ; Female ; Humans ; Neostriatum ; Neural Stem Cells ; Peptide Hydrolases ; Pregnancy ; Trypsin

Ampicillin, a beta-lactam antibiotic, has been reported to induce astrocytic glutamate transporter-1 which plays a crucial role in protecting neurons against glutamate excitotoxicity. We investigated the effect of ampicillin on neuronal damage in the mouse hippocampus and neostriatum following transient global forebrain ischemia. Male C57BL/6 mice were anesthetized with halothane and subjected to bilateral occlusion of the common carotid artery for 40 min. Ampicillin was administered post-ischemically (for 3 days) and/or pre-ischemically (for 3~5 days until one day before the onset of ischemia). Pre- and post-ischemic treatment with ampicillin (50 mg/kg/day or 200 mg/kg/day) prevented ischemic neuronal death in the medial CA1 area of the hippocampus as well as the neostriatum in a dose-dependent manner. In addition, ischemic neuronal damage was reduced by pre-ischemic treatment with ampicillin (200 mg/kg/day). In summary, our results suggest that ampicillin plays a functional role as a chemical preconditioning agent that protects hippocampal neurons from ischemic insult.
Ampicillin ; Animals ; Carotid Artery, Common ; Glutamic Acid ; Halothane ; Hippocampus ; Humans ; Ischemia ; Male ; Mice ; Neostriatum ; Neurons ; Prosencephalon

An attempt has been made to discriminate synaptic diversity in the neostriatum of the cat with emphasis on the characteristic structures of axon terminals and postsynaptic profiles. The differentiation of the axon terminals was based on the size and shape of synaptic vesicles in the axoplasm. Three types of axon terminals could be differentiated: Type I, the terminals contained small round (45 nm in diameter) vesicles; type II, the terminals with large pleomorphic (50 nm) vesicles; and type III, the terminals contained flattened (45 x 25 nm) vesicles. The type I terminals were making asymmetrical or symmetrical synapses in contact with the somata, dendrites and dendritic spines of neurons in the neostriatum, and a few type I terminals making asymmetrical or symmetrical contact with axons were also observed. The type II and III terminals were making symmetrical contact with the somata and dendrites of neostriatal neurons. A few type II terminals formed at the node of Ranvier of myelinated nerve fibers were making symmetrical contact with large dendrites. Additionally, dendro-dendritic and serial syanpses were rarely found in the neostriatum. In the serial synapses composed of axo-dendritic and dendro-dendritic synapses, the type I terminals making asymmetrical contact and the type II making symmetrical contact were identified.
Animals ; Axons ; Cats* ; Dendrites ; Dendritic Spines ; Neostriatum* ; Nerve Fibers, Myelinated ; Neurons ; Presynaptic Terminals ; Synapses ; Synaptic Vesicles

The secondary motor cortex (M2) encodes choice-related information and plays an important role in cue-guided actions. M2 neurons innervate the dorsal striatum (DS), which also contributes to decision-making behavior, yet how M2 modulates signals in the DS to influence perceptual decision-making is unclear. Using mice performing a visual Go/No-Go task, we showed that inactivating M2 projections to the DS impaired performance by increasing the false alarm (FA) rate to the reward-irrelevant No-Go stimulus. The choice signal of M2 neurons correlated with behavioral performance, and the inactivation of M2 neurons projecting to the DS reduced the choice signal in the DS. By measuring and manipulating the responses of direct or indirect pathway striatal neurons defined by M2 inputs, we found that the indirect pathway neurons exhibited a shorter response latency to the No-Go stimulus, and inactivating their early responses increased the FA rate. These results demonstrate that the M2-to-DS pathway is crucial for suppressing inappropriate responses in perceptual decision behavior.
Mice ; Animals ; Motor Cortex ; Corpus Striatum/physiology* ; Neostriatum ; Neurons/physiology* ; Reaction Time

The selective vulnerability of the basal ganglia to carbon monoxide(CO) is well recognized. And hyperbaric oxygen therapy(HBO) has long been accepted as a primary treatment for CO poisoning; however, the mechanism of action and objective methods to assess the therapeutic efhcacy of HBO have not been fully established. To evaluate the effect of HBO on the neurotransmitter changes in CO poisoning the striatal dopamine and its metabolites were measured in CO-intoxicated and HBO treated rats by high performance liquid chromatograpy with electrochemical detection. Male SpragueDawley rats, weighing 250-350 g were exposed to 4,500 ppm CO for 30 minutes and a group of them was treated with HBO(3 ATA, 30 miutes). The neostriatum of the rats were obtained and investigated according to the various time lapse after the cessation of CO exposure or the completion of HBO, The results are as follows: 1. The application of the routine HBO to the normal rat did not affect the levels of striatal neurotransmitters. 2. The concentration of striatal DA was markedly increased in CO-intoxicated rat during acute phase and it was reversed by HBO. But the effect did not last more than 24 hours. 3. In the delayed phase of experiment, the concentration of striatal DA tended to be decreased, which was partially thought to be due to the striatal injury, damage of striatonigral pathway or neuronal loss of substantia nigra by C0-intoxication.These results suggest that dopaminergic system might be implicated both in the pathogenesis of C0-induced striatal injury and the therapeutic efficacy of HB0.
Animals ; Basal Ganglia ; Carbon Monoxide* ; Carbon* ; Dopamine ; Humans ; Hyperbaric Oxygenation* ; Male ; Neostriatum ; Neurons ; Neurotransmitter Agents* ; Oxygen ; Poisoning ; Rats* ; Substantia Nigra

BACKGROUNDA new brain region, the marginal division (MrD), was discovered at the caudal margin of the neostriatum. The MrD was shown to be involved in learning and memory in the rat. The aim of this study was to investigate the expression of the immediate-early genes c-fos and c-jun in the MrD of the striatum during learning and memory processes in the rat, immunocytochemical and Western blot methods were used to examine Y-maze trained rats.

METHODSThe rats were divided into three groups, namely the training, pseudotraining, and control groups. After Y-maze training, the expression of the immediate-early genes c-fos and c-jun in the MrD of the rats was investigated using immunocytochemical and Western blot methods.

RESULTSAfter one hour of Y-maze training, the expression of c-jun and c-fos proteins was significantly enhanced in the MrD; the c-jun protein, in particular, was more intensely expressed in this region than in other parts of the striatum. The expression of these two proteins in the training group was significantly higher than in the pseudotraining and control groups. In addition, positive expression was also found in the hippocampus, cingulum cortex, thalamus, and in other areas. Western blot disclosed two immunoreactive bands for the anti-c-fos antibody (47 kD and 54 kD) and two immunoreactive bands for the anti-c-jun antibody (39 kD and 54 kD).

CONCLUSIONSThese results indicate that the immediate-early genes c-fos and c-jun participate in signal transduction during the learning and memory processes associated with Y-maze training in rats.

Animals ; Male ; Maze Learning ; Memory ; Neostriatum ; metabolism ; Proto-Oncogene Proteins c-fos ; biosynthesis ; Proto-Oncogene Proteins c-jun ; biosynthesis ; Rats ; Rats, Sprague-Dawley

OBJECTIVETo explore the impact of gender on the marginal division(MrD)of the neostriatum in healthy adults.

METHODSConventional magnetic resonance imaging(MRI),3D structure images,and resting-state function MRI(rs-fMRI)were performed in 64 health adults,who were divided into male group(n=28)and female group(n=26).MrD was defined using manual drawing on structure images,and was applied to the computation of functional connectivity maps.Single group data was performed with simple t test,and two groups data were performed with analysis of covariance with age as the covariance.

RESULTSThe brain regions of functional connectivity related with MrD were located in bilateral middle cingulate gyrus,rolandic operculum,insula,putamen,thalamus and amygdala in male group,and in bilateral heschl gyrus,putamen,thalamus and amygdala in female group.The brain regions with increased functional connectivity related with MrD were demonstrated in right superior temporal gyrus,middle temporal gyrus and gyrus rectus,and decreased in left superior parietal cortex in male group compared with that in female group.

CONCLUSIONThe functional connectivity related with MrD shows certain gender-related consistency and difference in the brain of health adults.

Adult ; Aged ; Aged, 80 and over ; Brain ; physiology ; Brain Mapping ; Female ; Humans ; Limbic System ; physiology ; Magnetic Resonance Imaging ; Male ; Middle Aged ; Neostriatum ; physiology ; Sex Factors ; Young Adult