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Abnormal oscillation in the cortical-basal ganglia loop is involved in the pathophysiology of parkinsonism. High-voltage spindles (HVSs), one of the main type abnormal oscillations in Parkinson's disease, are regulated by dopamine D2-like receptors but not D1-like receptors. However, little is known about how dopamine D2-like receptors regulate HVSs and the role of hyperpolarization-activated cyclic nucleotide-gated2 (HCN2) in HVSs regulation. We simultaneously recorded the local field potential (LFP) in globus pallidus (GP) and electrocorticogram (ECoG) in primary motor cortex (M1) in freely moving 6-hydroxydopamine (6-OHDA) lesioned or control rats. The expression of HCN2 and dopamine D2 receptor in the subthalamic nucleus (STN) was examined by immunochemical staining and Western blotting. We also tested the role of HCN2 in HVSs regulation by using pharmacological and shRNA methodology. We found that dopamine D2-like receptor agonists suppressed the increased HVSs in 6-OHDA lesioned rats. HCN2 was co-expressed with dopamine D2 receptor in the STN, and dopamine depletion decreased the expression of HCN2 as well as dopamine D2 receptor which contribute to the regulation of HVSs. HCN2 was down regulated by HCN2 shRNA, which thereby led to an increase in the HVSs in naïve rats while HCN2 agonist reduced the HVSs in 6-OHDA lesioned rats. These results suggest that HCN2 in the STN is involved in abnormal oscillation regulation between M1 cortex and GP., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Epilepsy is a chronic neurological disorder characterized by spontaneous recurrent seizures, which also occur in demyelinating diseases of the central nervous system (CNS) with a higher prevalence. Meanwhile, demyelination occurrings have been occasionally observed in CNS of epilepsy patients, indicating an association between demyelination and epileptic seizures by an unknown mechanism. However, no confirmative experimental evidence has yet been given. Thus, by using a rat pentylenetetrazol model, electroencephalogram (EEG), Western blotting, enzyme-linked immunosorbent assay (ELISA) and immunohistochemistry, the present study provided direct evidence that myelin sheath damage in rat hippocampus and cerebral cortex started in the early stage of epileptic seizures induction and lasted with no further increase in severity in the development of epileptic seizures. It was illustrated that myelin sheath damage was not the result of oligodendrocyte destruction, but the autoantibodies against myelin basic protein (MBP) produced in peripheral circulation accompanied by increased permeability of blood-brain barrier (BBB) formed in the development of epileptic seizures. This study firstly provided experimental evidence for myelin sheath damage in PTZ-induced rat's epileptic seizures and further demonstrated that its possible cause was autoimmunoreaction., (Copyright © 2011 Elsevier B.V. All rights reserved.)

The clinic treatment of epilepsy with epileptic foci overlapped with eloquent cortex is not satisfactory. In this study we investigated the direct effects of low- and high-frequency electric cortical stimulation (ECS) on ferric chloride-induced seizures in the experimental rats. Results showed that spontaneous seizures were observed in all rats during the EEG recording after the intracortical injection of ferric chloride solution into left sensorimotor cortex. One-hertz or 100-Hz ECS with 0.3 ms duration and 0.1 mA amplitude square pulses in 1h on the cortical lesioned area significantly decreased the number of seizures compared with that of the non-stimulation control group. The mean duration time of seizures in 1-Hz or 100-Hz groups was apparently shorter than that in the control group. In brief, this study showed that both low- and high-frequency ECS suppressed the seizures induced by ferric chloride in rats, indicating their potential treatment effects on epilepsy in clinic.

Abstract: In present study, in vivo electrophysiological techniques were applied to examine the effects of anterior cingulate cortex (ACC) activation on mechanical and electrical stimuli-evoked responses in rat spinal cord wide-dynamic-range (WDR) neurons. We found that bilateral ACC electrical stimulation (100Hz, 20V, 20s) had different effects on neuronal responses to brush, pressure and pinch stimuli (10s). The brush-evoked neuronal responses at baseline, post 1min and post 5min were 60.8±15.0, 59.2±15.4 and 60.0±19.3 spikes/10s, respectively (n =10, P >0.05 vs. baseline). The pressure-evoked neuronal responses at baseline, post 1min and post 5min were 77.8±11.9, 38.0±7.8 and 45.8±7.6 spikes/10s, respectively (n =10, P <0.05 vs. baseline). The pinch-evoked neuronal responses at baseline, post 1min and post 5min were 137.6±16.7, 62.6±17.5 and 68.8±15.0 spikes/10s, respectively (n =10, P <0.05 vs. baseline). Furthermore, ACC stimulation generated distinct effects on the different components of wind-up response. The total numbers of late response (LR) and after-discharge (AD), but not early response (ER), significantly decreased. Collectively, the present study demonstrated that short-term ACC activation could generate long-term inhibitory effects on the responses of WDR neurons to noxious mechanical (pressure and pinch) and electrical stimuli. The results indicated that ACC activation could negatively regulate noxious information ascending from spinal cord with long-term effect, providing potential neuronal substrate for the modulation of ACC activation on nociception. [Copyright &y& Elsevier]

Abstract: Objective: To evaluate the efficacy of Fluoro Jade-C staining (FJC) in the assessment of brain injury after deep hypothermia circulatory arrest (DHCA). Methods: Six healthy adult miniature male pigs underwent DHCA, the rectal temperature was down to 18°C, circulation was stopped , circulatory arrest was maintained for 60 minutes. On postoperative day 1, perfusion-fixation was performed on brain tissue. Cerebral cortex, hippocampus, cerebellum were taken for sampling. FJC, hematoxylin–eosin staining (HE), nissl staining (NISSL), terminal deoxynucleotidyl transferase biotin-dUTP nick end labeling (TUNEL) were performed to detect the histological and pathological changes. Histological scores of all slices were ranked. Comparison between the FJC and other techniques was done by analysis of variance (ANOVA) according to histological scores. Results: All animals survived the operation. On the cerebral cortex, in comparison of FJC between HE, NISSL and TUNEL, the p value was 0.90, 0.40, 0.16 respectively (p >0.05). On the hippocampus, the comparison of FJC with HE, NISSL and TUNEL had a p value of 0.12, 0.23, 0.62 respectively (p >0.05). On the cerebellum, in comparing FJC with HE, NISSL and TUNEL, the p value was 0.96, 0.77, 0.96 respectively (p >0.05). On representative regions, the results of FJC were in accordance with that of TUNEL, NISSL and HE. Furthermore, ascertainment of brain injury is easier with FJC. Conclusion: FJC is a reliable and convenient method to assess brain injury after DHCA. [ABSTRACT FROM AUTHOR]