Objective: To investigate the effect and significance of electroacupuncture (EA) on neuronal apoptosis and hindlimb motor and bladder functional improvement in rats with acute spinal cord injury (SCI). Methods: Sixty ...Objective: To investigate the effect and significance of electroacupuncture (EA) on neuronal apoptosis and hindlimb motor and bladder functional improvement in rats with acute spinal cord injury (SCI). Methods: Sixty healthy Sprague Dawley rats were randomly assigned to sham, model, EA, and EA control groups (n = 15 each). EA group rats received EA treatment at Zhibian and Shuidao acupoints seven times daily, whereas EA control group rats received EA at two points, 0.5 cm away from Zhibian and Shuidao, respectively. Histomorphological changes in spinal cord tissue were examined using hematoxylin-eosin staining. Neuronal apoptosis was detected by TUNEL assay. Bcl-2, Bax, and Bad protein levels were detected using immunohistochemistry. Additionally, hindlimb motor function, residual urine volume and maximum bladder capacity were measured. Results: HE staining revealed a morphologically and structurally intact spinal cord in the EA group, and the tissue contained scattered blood cells without edema. In the EA control group, there were small morphological defects in the spinal cord, and the tissue contained fewer blood cells with local edema. Compared with the EA control and model groups, Bax and Bad levels were significantly decreased in the EA group and Bcl-2 expression was increased (P < 0.05). After SCI, hindlimb function scores, residual urine volume, and maximum bladder capacity in rats of the EA group significantly differed from those of the EA control group (P < 0.05). Conclusion: EA may induce SCI-induced improvements in hindlimb motor and bladder functions by affecting neuronal apoptosis and relevant gene expression changes.展开更多
The discharge patterns of neurons in auditory centers encode information about sounds.However,few studies have focused on the synaptic mechanisms underlying the shaping of discharge patterns using intracellular record...The discharge patterns of neurons in auditory centers encode information about sounds.However,few studies have focused on the synaptic mechanisms underlying the shaping of discharge patterns using intracellular recording techniques.Here,we investigated the discharge patterns of inferior collicular(IC)neurons using intracellular recordings to further elucidate the mechanisms underlying the shaping of discharge patterns.Under in vivo intracellular recording conditions,recordings were obtained from 66 IC neurons in 18 healthy adult mice(Mus musculus,Km)under free field-stimulation.Fiftyeight of these neurons fired bursts of action potentials(APs)to auditory stimuli and the remaining eight just generated local responses such as excitatory(n=4)or inhibitory(n=4)postsynaptic potentials.Based on the APs and subthreshold responses,the discharge patterns were classified into seven types:phasic(24/58,41.4%),phasic burst(8/58,13.8%),pauser(4/58,6.9%),phasic-pauser(1/58,1.7%),chopper(2/58,3.4%),primary-like tonic(14/58,24.1%)and sound-induced inhibitory(5/58,8.6%).We concluded that(1)IC neurons exhibit at least seven distinct discharge patterns;(2)inhibition participates in shaping the discharge pattern of most IC neurons and plays a role in sculpting the pattern,except for the primary-like tonic pattern which was not shapedby inhibition;and(3)local neural circuits are the likely structural basis that shapes the discharge patterns of IC neurons and can be formed either in the IC or in lower-level auditory structures.展开更多
Ischemic postconditioning renders brain tissue tolerant to brain ischemia,thereby alleviating ischemic brain injury.However,the exact mechanism of action is still unclear.In this study,a rat model of global brain isch...Ischemic postconditioning renders brain tissue tolerant to brain ischemia,thereby alleviating ischemic brain injury.However,the exact mechanism of action is still unclear.In this study,a rat model of global brain ischemia was subjected to ischemic postconditioning treatment using the vessel occlusion method.After 2 hours of ischemia,the bilateral common carotid arteries were blocked immediately for 10 seconds and then perfused for 10 seconds.This procedure was repeated six times.Ischemic postconditioning was found to mitigate hippocampal CA1 neuronal damage in rats with brain ischemia,and up-regulate acid-sensing ion channel 2a expression at the m RNA and protein level.These findings suggest that ischemic postconditioning up-regulates acid-sensing ion channel 2a expression in the rat hippocampus after global brain ischemia,which promotes neuronal tolerance to ischemic brain injury.展开更多
文摘Objective: To investigate the effect and significance of electroacupuncture (EA) on neuronal apoptosis and hindlimb motor and bladder functional improvement in rats with acute spinal cord injury (SCI). Methods: Sixty healthy Sprague Dawley rats were randomly assigned to sham, model, EA, and EA control groups (n = 15 each). EA group rats received EA treatment at Zhibian and Shuidao acupoints seven times daily, whereas EA control group rats received EA at two points, 0.5 cm away from Zhibian and Shuidao, respectively. Histomorphological changes in spinal cord tissue were examined using hematoxylin-eosin staining. Neuronal apoptosis was detected by TUNEL assay. Bcl-2, Bax, and Bad protein levels were detected using immunohistochemistry. Additionally, hindlimb motor function, residual urine volume and maximum bladder capacity were measured. Results: HE staining revealed a morphologically and structurally intact spinal cord in the EA group, and the tissue contained scattered blood cells without edema. In the EA control group, there were small morphological defects in the spinal cord, and the tissue contained fewer blood cells with local edema. Compared with the EA control and model groups, Bax and Bad levels were significantly decreased in the EA group and Bcl-2 expression was increased (P < 0.05). After SCI, hindlimb function scores, residual urine volume, and maximum bladder capacity in rats of the EA group significantly differed from those of the EA control group (P < 0.05). Conclusion: EA may induce SCI-induced improvements in hindlimb motor and bladder functions by affecting neuronal apoptosis and relevant gene expression changes.
基金supported by grants from the National Natural Science Foundation of China (31070971,31000959)
文摘The discharge patterns of neurons in auditory centers encode information about sounds.However,few studies have focused on the synaptic mechanisms underlying the shaping of discharge patterns using intracellular recording techniques.Here,we investigated the discharge patterns of inferior collicular(IC)neurons using intracellular recordings to further elucidate the mechanisms underlying the shaping of discharge patterns.Under in vivo intracellular recording conditions,recordings were obtained from 66 IC neurons in 18 healthy adult mice(Mus musculus,Km)under free field-stimulation.Fiftyeight of these neurons fired bursts of action potentials(APs)to auditory stimuli and the remaining eight just generated local responses such as excitatory(n=4)or inhibitory(n=4)postsynaptic potentials.Based on the APs and subthreshold responses,the discharge patterns were classified into seven types:phasic(24/58,41.4%),phasic burst(8/58,13.8%),pauser(4/58,6.9%),phasic-pauser(1/58,1.7%),chopper(2/58,3.4%),primary-like tonic(14/58,24.1%)and sound-induced inhibitory(5/58,8.6%).We concluded that(1)IC neurons exhibit at least seven distinct discharge patterns;(2)inhibition participates in shaping the discharge pattern of most IC neurons and plays a role in sculpting the pattern,except for the primary-like tonic pattern which was not shapedby inhibition;and(3)local neural circuits are the likely structural basis that shapes the discharge patterns of IC neurons and can be formed either in the IC or in lower-level auditory structures.
文摘Ischemic postconditioning renders brain tissue tolerant to brain ischemia,thereby alleviating ischemic brain injury.However,the exact mechanism of action is still unclear.In this study,a rat model of global brain ischemia was subjected to ischemic postconditioning treatment using the vessel occlusion method.After 2 hours of ischemia,the bilateral common carotid arteries were blocked immediately for 10 seconds and then perfused for 10 seconds.This procedure was repeated six times.Ischemic postconditioning was found to mitigate hippocampal CA1 neuronal damage in rats with brain ischemia,and up-regulate acid-sensing ion channel 2a expression at the m RNA and protein level.These findings suggest that ischemic postconditioning up-regulates acid-sensing ion channel 2a expression in the rat hippocampus after global brain ischemia,which promotes neuronal tolerance to ischemic brain injury.