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

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

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

OBJECTIVETo discuss the protective effect of alkaloids from Piper longum (PLA) in rat dopaminergic neuron injury of 6-OHDA-induced Parkinson's disease and its possible mechanism.

METHODThe rat PD model was established by injecting 6-OHDA into the unilateral striatum with a brain solid positioner. The PD rats were divided into the PLA group (50 mg x kg(-1) x d(-1)), the madorpa group (50 mg x kg(-1) x d(-1)) and the model group, with 15 rats in each group. All of the rats were orally given drugs once a day for 6 weeks. Meanwhile, other 15 rats were randomly selected as the sham operation group, and only injected with normal saline in the unilateral striatum. The behavioral changes were observed with the apomorphine (APO)-induced rotation and rotary rod tests. The number of tyrosine hydroxylase (TH)-positive cells in rat substantia nigra and the density of TH-positive fibers in striatum were detected by tyrosine hydroxylase immunohistochemistry. The content of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), glutathione (GSH), catalase (CAT), malondialdehyde (MDA), nitric oxide (NO) and nitric oxide synthase (NOS) in rat substantia nigra and striatum were measured by the spectrophotometric method.

RESULTAfter being induced by APO, PD rats showed obvious rotation behaviors, with decreased time stay on rotary rod and significant reduction in the number of TH-positive cells in sustantia nigra and the density of TH-positive fibers in striatum. The activities of SOD, GSH-Px, CAT, the content of GSH and the total antioxidant capacity significantly decreased, whereas the activities of NOS and the content of MDA, NO significantly increased. PLA could significantly improve the behavioral abnormality of PD rats and increase the number of TH-positive cells in sustantia nigra and the density of TH-positive fibers in striatum. It could up-regulate the activities of SOD, GSH-Px, CAT, the content of GSH and the total antioxidant capacity, and decrease the content of NOS and the content of MDA, NO.

CONCLUSIONAlkaloids from P. longum shows the protective effect in substantia nigra cells of 6-OHDA-induced PD model rats. Its mechanism may be related with their antioxidant activity.

Administration, Oral ; Alkaloids ; administration & dosage ; pharmacology ; Animals ; Apomorphine ; pharmacology ; Catalase ; metabolism ; Dopamine Agonists ; pharmacology ; Dopaminergic Neurons ; drug effects ; metabolism ; pathology ; Glutathione ; metabolism ; Glutathione Peroxidase ; metabolism ; Male ; Malondialdehyde ; metabolism ; Motor Activity ; drug effects ; Neostriatum ; drug effects ; metabolism ; Nitric Oxide ; metabolism ; Nitric Oxide Synthase ; metabolism ; Oxidopamine ; Parkinson Disease, Secondary ; chemically induced ; physiopathology ; prevention & control ; Piper ; chemistry ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Substantia Nigra ; drug effects ; metabolism ; Superoxide Dismutase ; metabolism ; Tyrosine 3-Monooxygenase ; metabolism

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

OBJECTIVETo observe the analgesic effect of sinomenine on the neuropathic pain rat model induced by SSNI, and discuss its impact on monoamine neurotransmitters in striatal extracellular fluid.

METHODMale SD rats were randomly divided into the sham operation group, the SSNI model group, the gabapentin group (100 mg x kg(-1)), the sinomenine high dose group (40 mg x kg(-1)) and the sinomenine low dose group (20 mg x kg(-1)). Mechanical hyperalgesia and cold pain sensitivity were evaluated by Von Frey hairs and cold spray. Striatum was sampled by microdialysis. High performance liquid chromatography-electrochemical detector (HPLC-ECD) were used to detect the content of such neurotransmitters as monoamine neurotransmitters noradrenaline (NE), dopamine (DA), 5-hydroxy tryptamine (5-HT) and their metabolites dihydroxyphenylacetic phenylacetic acid (DOPAC) and 5-hydroxyindoleacetic acid (5-HIAA).

RESULTSSNI model rats showed significant improvement in mechanical withdrawal threshold and cold pain sensitivity, significant decrease in intracerebral NE and notable increase in DA, 5-HT and their metabolites. Compared with the model group, the sinomenine high dose group showed significant increase in mechanical withdrawal threshold at 60, 90, 180 and 240 min after abdominal administration (P < 0.01), significant decrease in cold pain sensitivity score during 30-240 min (P < 0.05). Sinomenine can significantly up-regulated NE content in striatal extracellular fluid during 45-135 min (P < 0.05), remarkably reduce DA content and DOPAC at 45, 75 and 135 min (P < 0.05), 5-HT content during 45-135 min, DOPAC during 75-165 min (P < 0.05), and 5-HIAA during 45-135 min (P < 0.05).

CONCLUSIONSinomenine has the intervention effect on neuropathic pain in SSNI model rats. Its mechanism may be related to disorder of monoamine neurotransmitters in striatal extracellular fluid.

Analgesics ; pharmacology ; Animals ; Biogenic Monoamines ; metabolism ; Disease Models, Animal ; Extracellular Fluid ; drug effects ; Male ; Morphinans ; pharmacology ; Neostriatum ; pathology ; Neurotransmitter Agents ; metabolism ; Rats ; Rats, Sprague-Dawley ; Sciatic Nerve ; drug effects ; injuries ; metabolism ; pathology

OBJECTIVETo observe the influence of borneol, a traditional Chinese medicine, on the concentration of ceftriaxone in the rat brain striatum and evaluate the relativity.

METHODThe sample of cerebrospinal fluid in the rat brain striatum was collected via brain microdialysis technology, and then the contents of ceftriaxone in standard preparation and sample were detected by high efficiency liquid chromatography combined with diode array detector respectively and analyzed statistically. The concentration of ceftriaxone in rat brain striatum in the ceftriaxone + Borneol group was compared with that in the ceftriaxone-only group.

RESULTThe concentration of ceftriaxone in the rat brain in the ceftriaxone + Borneol group (13.01-4.43 mg x L(-1)) is significantly higher than that in the ceftriaxone-only group (2.41-0.94 mg x L(-1)).

CONCLUSIONBorneol can promote ceftriaxone through blood-brain barrier, and increase the concentration thereof in striatum.

2-Pyridinylmethylsulfinylbenzimidazoles ; pharmacokinetics ; Animals ; Blood-Brain Barrier ; Bornanes ; pharmacology ; Ceftriaxone ; pharmacology ; Chromatography, High Pressure Liquid ; Corpus Striatum ; drug effects ; metabolism ; Drug Combinations ; Male ; Medicine, Chinese Traditional ; Microdialysis ; Neostriatum ; drug effects ; metabolism ; Rats ; Rats, Wistar

OBJECTIVETo understand the action mechanism of Tianwang Buxin decoction that is the whole prescription included all drugs from Tianwang Buxin honeyed pill and Tianwang Buxin without radix platycodi decoction on the nerves-calming and hyposomnia-curing.

METHODThe influence of Tianwang Buxin decoction and Tianwang Buxin without radix platycodi decoction on somnus utilizing the mice' s somnus in coordination with Pentobarbital sodium was observed. Investigation whether the compatibility of radix platycodi affect the concentration of brain neurotransmitter, 5-HT, NA and DA, correlated sleep-awareness by HPLC-ECD detection was carried out after rats' hyposomnia model were founded.

RESULTThe falling asleep rates of mice given subthreshold dose raised (P<0.05), remarkably because of Tianwang Buxin decoction. But there is significant difference with Tianwang Buxin lack of radix platycodi decoction despite the heightening tendency. All groups were discovered that the level of 5-HT and 5-HIAA, the monoamine transmitter, heighten obviously after the whole prescription and the prescription without radix platycodi were administered in nuclei raphae medullae oblongatae (P<0.05), but it is only the whole prescription group that emerged same phenomenon in the Ammon's horn and striatum area. Furthermore significant difference exist as comparing Tianwang Buxin whole prescription decoction with Tianwang Buxin without radix platycodi decoction. The level of another monoamine transmitter DA stepped up notably in the whole prescription and the prescription without radix platycodi groups following administration in corpora striata (P<0.05).

CONCLUSIONThe mechanism of hypnosis action lie in enhancement of releasing 5-HT in encephalic regions for the Tianwang Buxin whole prescription decoction, but it's possible that radix platycodi may be the key point that adjusts the additional quantity.

Animals ; Brain ; drug effects ; metabolism ; Dose-Response Relationship, Drug ; Drug Compounding ; methods ; Drugs, Chinese Herbal ; administration & dosage ; pharmacology ; therapeutic use ; Female ; Hippocampus ; drug effects ; metabolism ; Male ; Neostriatum ; drug effects ; metabolism ; Neurotransmitter Agents ; metabolism ; Rats ; Sleep Initiation and Maintenance Disorders ; drug therapy ; metabolism ; pathology

OBJECTIVETo study the effect of the Chinese compound prescription Ginkgo biloba Pingchan Recipe (GBPR) on experimental Parkinson disease (PD) in mice and explore the possible mechanism.

METHODSMale C57/BL6J mice were divided into normal control, PD model and treatment groups. PD model was established by intraperitoneal injection with 1-methl-4-phenyl-1,2,3,6-tetrahydropyridin (MPTP) in the mice, and in the treatment group, GBPR was administered intragastrically after the injection. The mice were sacrificed 14 and 28 days later, and using in situ hybridization with Digoxin-labeled nNOS cDNA oligonucleotide probe, neuronal nitric oxide synthase (nNOS) mRNA was detected in the striatum and substantia nigra in the brain of mice.

RESULTSnNOS mRNA expression was detected in the striatum and substantia nigra of the PD model mice, and GBPR treatment significantly reduced its expressions.

CONCLUSIONGBPR has obvious inhibitory effect against the neurotoxicity of NO probably by producing an anti-oxiditive effect through decreasing nNOS synthesis in the brain.

Animals ; Brain ; drug effects ; enzymology ; metabolism ; Disease Models, Animal ; Drugs, Chinese Herbal ; pharmacology ; Gene Expression Regulation, Enzymologic ; drug effects ; Ginkgo biloba ; chemistry ; Male ; Mice ; Mice, Inbred C57BL ; Neostriatum ; drug effects ; metabolism ; Nitric Oxide Synthase Type I ; genetics ; Parkinson Disease ; enzymology ; genetics ; metabolism ; RNA, Messenger ; genetics ; metabolism ; Substantia Nigra ; drug effects ; metabolism

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