OBJECTIVE: To elucidate the modulation mechanism of Suanzaoren Decoction (SZRD) on basolateral amygdala (BLA) neuronal activity to alleviate chronic restraint stress (CRS)-related behavioral deficits. METHODS: The male C57BL/6J mice were assigned to 4 groups using the complete randomization method, including control (CON, n=19), CRS (n=19), SZRD (n=21), and fluoxetine (Flu, n=22) groups. Mice were restrained for 6 h per day, over a 21-d period to establish CRS models. The CON group remained in their cages without food or water during the 6-h matching period. SZRD and Flu groups received intragastric administration of SZRD (4.68 g/kg) and Flu (20 mg/kg) daily, respectively, 30 min before restraint for 21 consecutive days. The therapeutic effects of SZRD were evaluated using behavioral tests including the tail suspension test, elevated plus maze test, and forced swimming test. The cellular Fletcher B. Judson murine osteosarcoma proto-oncogene (c-Fos) expression in the BLA was measured using immunofluorescence, while action potential (AP) firing and synaptic transmission in BLA pyramidal neurons were evaluated using whole-cell patch-clamp recordings. RESULTS: SZRD administration significantly increased time spent in the open arms and open-arm entries while reducing immobility time (P<0.05 or P<0.01). It downregulated CRS-induced c-Fos expression and AP firing of pyramidal neurons in the BLA (P<0.01). Additionally, SZRD selectively attenuated excitatory (P<0.01), but not inhibitory, synaptic transmission onto BLA pyramidal neurons. CONCLUSION SZRD alleviated CRS-induced anxiety- and depression-like behaviors in mice by modulating the excitability and synaptic transmission of BLA pyramidal neurons.
Animals ; Drugs, Chinese Herbal/therapeutic use* ; Depression/complications* ; Pyramidal Cells/pathology* ; Male ; Mice, Inbred C57BL ; Basolateral Nuclear Complex/pathology* ; Restraint, Physical ; Anxiety/complications* ; Behavior, Animal/drug effects* ; Stress, Psychological/physiopathology* ; Mice ; Proto-Oncogene Proteins c-fos/metabolism* ; Action Potentials/drug effects* ; Synaptic Transmission/drug effects*

OBJECTIVE: To investigate the effects of acid-sensing ion channels (ASICs) on electrophysiological epileptic activities of mouse hippocampal pyramidal neurons in the extracellular acidotic condition. METHODS: We investigated effects of extracellular acidosis on epileptic activities induced by elevated extracellular K concentration or the application of an antagonist of GABA receptors in perfusate of mouse hippocampal slices under field potential recordings. We also tested the effects of extracellular acidosis on neuronal excitability under field potential recording and evaluated the changes in epileptic activities of the neurons in response to pharmacological inhibition of ASICs using a specific inhibitor of ASICs. RESULTS: Extracellular acidosis significantly suppressed epileptic activities of the hippocampal neurons by converting ictal-like epileptic activities to non-ictal-like epileptic activities in both high [K ]o and disinhibition models, and also suppressed the intrinsic excitability of the neurons. ASICs inhibitor did not antagonize the inhibitory effect of extracellular acidosis on ictal epileptic activities and intrinsic neuronal excitability, but exacerbated non-ictal epileptic activities of the neurons in extracellular acidotic condition in both high [K]o and disinhibition models. CONCLUSIONS ASICs can differentially modulate ictal-like and non-ictallike epileptic activities via its direct actions on excitatory neurons.
Acid Sensing Ion Channels ; metabolism ; Acidosis ; Animals ; Epilepsy ; physiopathology ; Hydrogen-Ion Concentration ; Mice ; Pyramidal Cells ; pathology ; physiology

Cognition and pain share common neural substrates and interact reciprocally: chronic pain compromises cognitive performance, whereas cognitive processes modulate pain perception. In the present study, we established a non-drug-dependent rat model of context-based analgesia, where two different contexts (dark and bright) were matched with a high (52°C) or low (48°C) temperature in the hot-plate test during training. Before and after training, we set the temperature to the high level in both contexts. Rats showed longer paw licking latencies in trials with the context originally matched to a low temperature than those to a high temperature, indicating successful establishment of a context-based analgesic effect in rats. This effect was blocked by intraperitoneal injection of naloxone (an opioid receptor antagonist) before the probe. The context-based analgesic effect also disappeared after optogenetic activation or inhibition of the bilateral infralimbic or prelimbic sub-region of the prefrontal cortex. In brief, we established a context-based, non-drug dependent, placebo-like analgesia model in the rat. This model provides a new and useful tool for investigating the cognitive modulation of pain.
Action Potentials ; drug effects ; physiology ; Analgesics ; pharmacology ; therapeutic use ; Animals ; Disease Models, Animal ; Electric Stimulation ; Female ; In Vitro Techniques ; Naloxone ; pharmacology ; Narcotic Antagonists ; pharmacology ; Optogenetics ; Pain ; drug therapy ; pathology ; physiopathology ; Pain Measurement ; drug effects ; Pain Threshold ; drug effects ; physiology ; Patch-Clamp Techniques ; Physical Stimulation ; Prefrontal Cortex ; drug effects ; metabolism ; pathology ; Pyramidal Cells ; drug effects ; physiology ; Rats ; Rats, Sprague-Dawley ; Time Factors

The prenatal ethanol exposure induced the alterations of dendritic spine and synapse in visual cortex and their long-term effect would be investigated in mice from P0 to P30. Pregnant mice were intubated ethanol daily from E5 through the pup's birth to establish mode of prenatal alcohol abuse. The dendritic spines of pyramidal cells in visual cortex of pups were labeled with DiI diolistic assay, and the synaptic ultrastructure was observed under transmission electron microscope. Prenatal alcohol exposure was associated with a significant decrease in the number of dendritic spines of pyramidal neurons in the visual cortex and an increase in their mean length; ultrastructural changes were also observed, with decreased numbers of synaptic vesicles, narrowing of the synaptic cleft and thickening of the postsynaptic density compared to controls. Prenatal alcohol exposure is associated with long-term changes in dendritic spines and synaptic ultrastructure. The changes were dose-dependent with long term effect even at postnatal 30.
Animals ; Dendritic Spines ; ultrastructure ; Ethanol ; toxicity ; Female ; Fetal Alcohol Spectrum Disorders ; etiology ; pathology ; Male ; Mice ; Mice, Inbred C57BL ; Microscopy, Confocal ; Microscopy, Electron, Transmission ; Pregnancy ; Prenatal Exposure Delayed Effects ; pathology ; Pyramidal Cells ; ultrastructure ; Synapses ; ultrastructure ; Visual Cortex ; ultrastructure

OBJECTIVETo study the effects and possible mechanisms of effective composite of Naodesheng (NDS) on permanent cerebral ischemia-induced injury in rats.

METHODSMale Sprague-Dawley rats: with middle cerebral artery occlusion (MCAO) were established with the modified suture method, and they were randomly divided into the following groups: the sham-operated group, the model group, the Nimodipine group (0.012 g/kg), the NDS group (1.075 g/kg), the total extracts group (0.23 g/kg), the high-dose NEC group (0.07 g/kg), the middle-dose NEC group (0.02 g/kg), and the low-dose NEC group (0.007 g/kg). The aforesaid medicines were administered at the 2nd, 4th, and 24th h after focal cerebral ischemia, and the infarction size and water content in the brain were evaluated at the 26th h after MCAO. Then, after oral administration once daily for 7 successive days, the changes in the degree of neurological deficit, oxidative stress, and apoptosis were measured on the 7th day.

RESULTSNEC could significantly reduce the infarction size after focal cerebral ischemia, and slightly relieve water content in the brain, significantly alleviate neurological function impairment, increase the levels of superoxide dismutase (SOD) and adenosine triphosphate enzyme (ATPase) activity, and decrease the content of malondialdehyde (MDA). NEC could also extenuate Bax and caspase-3 expression in the hippocampus tissue of the ischemic region. As compared with the three NEC treated groups, the high-dose NEC showed better efficacy.

CONCLUSIONSNEC could significantly reduce brain injury induced by ischemia;: its mechanism was closely associated with hindering oxidative stress and apoptosis. The effective composite-guided methodology is a feasible tool to improve the neuro-protective properties of the Chinese medicine guided prescription NDS against focal cerebral ischemia in rats.

Adenosine Triphosphatases ; metabolism ; Animals ; Blotting, Western ; Brain Ischemia ; prevention & control ; Caspase 3 ; metabolism ; Drugs, Chinese Herbal ; pharmacology ; Hippocampus ; enzymology ; metabolism ; pathology ; Male ; Malondialdehyde ; metabolism ; Neuroprotective Agents ; pharmacology ; Pyramidal Cells ; drug effects ; Rats ; Rats, Sprague-Dawley ; Superoxide Dismutase ; metabolism ; bcl-2-Associated X Protein ; metabolism

The present study was undertaken to investigate the role of glial glutamate transporter-1 (GLT-1) in the brain ischemic tolerance induced by cerebral ischemic preconditioning (CIP) by observing the effect of GLT-1 antisense oligodeoxynucleotides (AS-ODNs) on the neuro-protection of CIP against brain ischemic insult in rats. Wistar rats with permanently occluded bilateral vertebral arteries were randomly assigned to 7 groups: (1) Sham group: the bilateral common carotid arteries (BCCA) were separated, but without occluding the blood flow; (2) CIP group: the BCCA were clamped for 3 min; (3) Brain ischemic insult group: the BCCA were clamped for 8 min; (4) CIP+brain ischemic insult group: 3 min CIP was preformed 2 d prior to 8 min ischemic insult; (5) Double distilled water group: 5 muL double distilled water was injected into the right lateral cerebral ventricle 12 h before, 12 h and 36 h after the BCCA was separated (but without occluding the blood flow), respectively; (6) AS-ODNs group: 5 microL AS-ODNs solution was injected into the right lateral cerebral ventricle 12 h before, 12 h and 36 h after the BCCA was separated (but without occluding the blood flow), respectively. This group was further divided into 9 nmol and 18 nmol subgroups according to the doses of AS-ODNs; (7) AS-ODNs+CIP+brain ischemic insult group: 5 microL AS-ODNs solution was injected into the right lateral cerebral ventricle 12 h before, 12 h and 36 h after CIP, respectively. This group was also further divided into 9 nmol and 18 nmol subgroups according to the doses of AS-ODNs. The other treatments were the same as those in CIP+brain ischemic insult group. The effect of the AS-ODNs on the expression of GLT-1 was assayed by using Western blot analysis. The profile of delayed neuronal death (DND) of pyramidal neurons in the CA1 hippocampus was evaluated by using thionin staining under light microscope by determining the neuronal density (ND) and histological grade (HG). Western blot analysis showed that AS-ODNs injected into the lateral cerebroventricle inhibited the expression of GLT-1 in the CA1 hippocampus in a dose-dependent manner. Neuropathological evaluation showed that there was no apparent DND in sham and CIP groups. Obvious DND of pyramidal neurons was found in brain ischemic insult group, which was represented by an increase in HG and a decrease in ND. CIP effectively protected the pyramidal neurons in the CA1 hippocampus against DND normally induced by ischemic insult, which indicating that CIP induced ischemic tolerance on the pyramidal neurons in the CA1 hippocampus. However, the injection of AS-ODNs into the lateral cerebroventricle blocked the neuro-protection of CIP against DND induced by brain ischemic insult. These results further proved the role of GLT-1 in the brain ischemic tolerance induced by CIP in rats.
Animals ; Brain ; pathology ; Brain Ischemia ; drug therapy ; CA1 Region, Hippocampal ; pathology ; Excitatory Amino Acid Transporter 2 ; metabolism ; Ischemic Preconditioning ; Oligodeoxyribonucleotides ; pharmacology ; Oligonucleotides, Antisense ; pharmacology ; Pyramidal Cells ; metabolism ; Rats ; Rats, Wistar

AIMTo investigate the effect of baicalin on the hippocampal neuronal apoptosis and the expression of HSP70 in rats with focal brain ischemia-reperfusion injury.

METHODSOne hundred and twenty male Wistar rats were randomly divided into six groups:sham operated group, ischemia-reperfusion group, nimodipine group and three baicalin groups,to which baicalin was administered at doses of 50, 100 and 200 mg x kg(-1), separately. The models of focal brain ischemia-reperfusion injury induced by middle cerebral artery occlusion (MCAO) were used in this study. HE stain was used to observe the pathological changes. Flow cytometry (FCM) was used for determination of neuronal apoptosis. HSP70 protein expression of the neurons was detected with immunohistochemistry. Reverse transcription polymerase chain reaction (RT-PCR) was used to detect the expression of the mRNA level of HSP70.

RESULTSBaicalin can significantly relieve the pathological changes and inhibit apoptosis in hippocampus CA1 area, and at the same time increase the expression of HSP70 and HSP70 mRNA.

CONCLUSIONBaicalin can relieve brain damage induced by focal brain ischemia-reperfusion in rats, which may be related to inhibiting the process of the neuronal apoptosis. The mechanism of antiapoptosis effect of baicalin may be related to the promotion of transcription of HSP70 mRNA and increasing the expression of the protein.

Animals ; Apoptosis ; drug effects ; Flavonoids ; isolation & purification ; pharmacology ; Flow Cytometry ; HSP70 Heat-Shock Proteins ; biosynthesis ; genetics ; Hippocampus ; drug effects ; metabolism ; pathology ; Infarction, Middle Cerebral Artery ; complications ; Male ; Neurons ; drug effects ; metabolism ; pathology ; Neuroprotective Agents ; isolation & purification ; pharmacology ; Plants, Medicinal ; chemistry ; Pyramidal Cells ; drug effects ; metabolism ; pathology ; RNA, Messenger ; biosynthesis ; genetics ; Random Allocation ; Rats ; Rats, Wistar ; Reperfusion Injury ; etiology ; genetics ; metabolism ; Reverse Transcriptase Polymerase Chain Reaction ; Scutellaria ; chemistry

OBJECTIVEKetogenic diet (KD) is a high fat, low protein, low carbohydrate diet. Its antiepileptic effect is certain but the underlying mechanism is unknown. The aim of the study was to reveal the possible mechanism from the view points of synaptic reorganization and GluR(5) expression in hippocampus.

METHODSEpilepsy was induced in Sprague-Dawley rats by kainic acid at postnatal day 28, all control animals were fed with normal rodent chow, whereas experimental rats were fed with ketogenic feed for 8 weeks. Spontaneous recurrent seizures were recorded. Mossy fiber sprouting and neuron damage in hippocampus were investigated by Timm staining and Nissl staining. Western blot and RT-PCR methods were applied to detect the expression of GluR(5) and GluR(5) mRNA in hippocampus.

RESULTSKD-fed rats (1.40 +/- 1.03) had significantly fewer spontaneous recurrent seizures than control diet-fed rats (7.36 +/- 3.75). The mean A of mossy fiber sprouting in the inner molecular layer of dentate gyrus was markedly higher in KA induced animals than that in saline control animals but it was similar in different diet fed groups. No significant differences were found in the mean A of Timm staining in CA(3) area and Nissl staining of neuron in hilus, CA(3) and CA(1) area. After KA kindling, KD-fed animals [(189.38 +/- 40.03)/mg pro] had significantly higher GluR(5) expression in hippocampus than control diet-fed animals [(128.79 +/- 46.51)/mg pro] although their GluR(5) mRNA was the same.

CONCLUSIONMossy fiber sprouting may be responsible for epileptogenesis in KA induced model and KD can suppress seizures in these animals. KD may upregulate young rat GluR(5) in inhibitory interneurons of CA(1) thus lead to an increased inhibition to prevent the propagation of seizure.

Animals ; Blotting, Western ; CA1 Region, Hippocampal ; metabolism ; pathology ; CA3 Region, Hippocampal ; metabolism ; pathology ; Chromosome Pairing ; drug effects ; Dentate Gyrus ; metabolism ; pathology ; Diet, Ketogenic ; methods ; Disease Models, Animal ; Epilepsy ; chemically induced ; diet therapy ; genetics ; metabolism ; pathology ; Excitatory Amino Acid Agonists ; Hippocampus ; drug effects ; metabolism ; pathology ; Kainic Acid ; Male ; Mossy Fibers, Hippocampal ; metabolism ; pathology ; Pyramidal Cells ; metabolism ; pathology ; RNA, Messenger ; metabolism ; Rats ; Receptors, Kainic Acid ; genetics ; metabolism ; Reverse Transcriptase Polymerase Chain Reaction

OBJECTIVETo observe protective effects of Shenmai (SM) injection on the delayed injury of the cerebral neurons in rat with intracerebral hemorrhage.

METHODRosenberg models of intracerebral hemorrhage was established and the effects of SM injection on the pathologic changes in neuronal structure, mitochondria-DNA(mtDNA)deletion, C-myc gene and expression PDGF-A gene in hippocampal CA1 areas, were investigated.

RESULTSM injection inhibited the apoptosis of pyramidal cells in the hippocampal CA1 areas, and decreased the degree of mtDNA deletion in the neurons in the injured area. SM injection had no effect on gene expression of C-myc at initial stage a intracerebral hemorrhage, but significantiy decreased the level of PDGF-A mRNA and prolonged the time of its expression.

CONCLUSIONSM injection might attenuate the delayed injury induced by intracerebral hemorrhage via regulating the expression of PDGF.

Animals ; Apoptosis ; drug effects ; Cerebral Hemorrhage ; metabolism ; pathology ; DNA, Mitochondrial ; genetics ; Drug Combinations ; Drugs, Chinese Herbal ; administration & dosage ; pharmacology ; Gene Deletion ; Hippocampus ; pathology ; Male ; Neurons ; drug effects ; Neuroprotective Agents ; administration & dosage ; pharmacology ; Ophiopogon ; chemistry ; Panax ; chemistry ; Plants, Medicinal ; chemistry ; Platelet-Derived Growth Factor ; biosynthesis ; genetics ; Pyramidal Cells ; pathology ; RNA, Messenger ; biosynthesis ; genetics ; Rats ; Rats, Sprague-Dawley

The purpose of this study was to investigate the effects of limb ischemic preconditioning (LIP) on apoptosis of pyramidal neurons in the CA1 hippocampus induced by global cerebral ischemia-reperfusion in rats. Forty-six rats whose bilateral vertebral arteries were occluded permanently were assigned to one of four groups: sham group, limb ischemia group, cerebral ischemia group and LIP group. LIP was performed by occluding the bilateral femoral arteries for 10 min 3 times in an interval of 10 min. Global cerebral ischemia was underwent by occluding the bilateral common carotid arteries for 8 min immediately after LIP. Assays for apoptosis of the hippocampal neurons were biologically and morphologically performed using gel electrophoresis, TUNEL and AO/EB staining. Characteristic DNA ladder was clearly visualized with gel electrophoresis in the hippocampus in cerebral ischemia group, but not in LIP group. The number of TUNEL-positive cells in the CA1 hippocampus was significantly reduced by LIP from 69.8+/-12 (cerebral ischemia group) to 17.8+/-5.8 (P<0.01). AO/EB staining also showed a reduction of apoptosis in LIP group compared with cerebral ischemia group. These results suggest that LIP can inhibit hippocampal neuronal apoptosis induced by cerebral ischemia-reperfusion, which contributes to the protection against the delayed neuronal death induced by cerebral ischemic insult.
Animals ; Apoptosis ; physiology ; Brain Ischemia ; physiopathology ; Hippocampus ; pathology ; Ischemic Preconditioning ; methods ; Lower Extremity ; blood supply ; Male ; Neurons ; pathology ; Pyramidal Cells ; pathology ; Rats ; Rats, Wistar ; Reperfusion Injury ; prevention & control