BACKGROUND： Previous studies have confirmed that fastigial nucleus electrical stimulation can induce endogenous neuroprotective mechanisms and produce wide and long-lasting neuroprotective effects. Nevertheless, the ...BACKGROUND： Previous studies have confirmed that fastigial nucleus electrical stimulation can induce endogenous neuroprotective mechanisms and produce wide and long-lasting neuroprotective effects. Nevertheless, the precise mechanisms remain poorly understood. OBJECTIVE： This study was designed to observe the effects of fastigial nucleus electrical stimulation on nestin-positive cell expression in adult rat lateral ventricle after focal cerebral ischemia/reperfusion, as well as neurological functional changes as a function of time. DESIGN： A randomized controlled animal experiment. SETTING： Department of Neurology, First Affiliated Hospital of Chongqing Medical University; Chongqing Key Laboratory of Neurology. MATERIALS： This study was performed in the Department of Neurology, First Affiliated Hospital of Chongqing Medical University and Chongqing Key Laboratory of Neurology from September 2004 to February 2006. A total of 180 healthy, adult, male Wistar rats, aged 8 weeks old, were provided by the Laboratory Animal Center of Chongqing Medical University. The main reagents and equipments were as follows： rabbit anti-rat nestin monoclonal antibody （Wuhan Boster Company, China）. METHODS： The included male Wistar rats were randomly divided into 5 groups： normal control, sham-operated, model, fastigial nucleus sham-stimulation （sham-stimulation for short）, and fastigial nucleus electrical stimulation （stimulation for short） groups. Six time points （1 hour of ischemia and 1, 3, 7, 14, 21, and 28 days of reperfusion, 6 rats per time point） were allotted to each group. Cerebral ischemia/reperfusion was performed by occlusion to the right middle cerebral artery with suture, followed by suture removal. In the stimulation group, subsequent to reperfusion, the rat left cerebellar fastigial nucleus was immediately subjected to 1 hour of stimulation. After anesthesia, the rat left cerebellar fastigial nucleus was stimulated for 1 hour using a square-wave electronic stimulator with a current intensity of 50 μ A, frequency of 50-100 Hz, and duration of 0.5 ms. In the sham-stimulation group, the procedure was identical to the stimulation group, except the needle was retained for 1 hour and current stimulation was withdrawn. In the model group, rats were subjected to cerebral ischemia/reperfusion, but electrical stimulation was omitted. In the sham-operated group, the internal carotid artery, rather than the middle cerebral artery, was inserted with suture, and simultaneously, electrical stimulation was omitted. In the normal control group, the rats received no treatments. MAIN OUTCOME MEASURES： Nestin-positive cells were detected by immunohistochemical staining in the rat ischemic lateral cerebral ventricle at 1, 3, 7, 14, 21, and 28 days post-reperfusion. RESULTS： Morphological changes of nestin-positive cells in the ischemic lateral ventricle： in the normal control group, very few nestin-positive cells were detected in the choroid plexus, ependyma, and subependymal region of the lateral ventricle. In the model group, the number of nestin-positive cells exhibited a tendency towards a single peak, i.e., cells increased at day 1, reached peak levels by day 7, and then decreased sharply. Fastigial nucleus electrical stimulation was administered following focal cerebral ischemia/reperfusion, and results revealed that nestin-positive cell morphology was similar to horizontal cell morphology on day 7. The number of nestin-positive cells decreased after 14 days; however, the proportion of horizontal cell-like cells increased. In the sham-stimulation group, there was no change in nestin-positive cells, nestin-positive cell expression in the ischemic lateral ventricle： nestin-positive cell expression increased in the ischemic lateral cerebral ventricle, exhibiting a tendency towards unimodality; the number of cells peaked on day 7 （P 〈 0.01） and gradually decreased after 14 days （P 〈 0.01）. Following fastigial nucleus electrical stimulation, the number of nestin-positive cells increased significantly （P 〈 0.05-0.01）, reached peak levels by day 7 （P 〈 0.01）, and remained at very high levels after 14 days （P 〈 0.01）. Neurofunctional changes： neurofunctional deficits were gradually alleviated with prolonged focal cerebral ischemia/reperfusion time. At 1 hour of ischemia, and 6 hours to 7 days of reperfusion, rat neurological scores were significantly lower in the stimulation group than in the model and sham-operation groups （P 〈 0.05-0.01）. CONCLUSION： Fastigial nucleus electrical stimulation increased nestin-positive cells in the rat lateral ventricle after focal cerebral ischemia/reperfusion in a time-dependent manner and simultaneously improved neurological deficits, as well as promoted differentiation of nestin-positive cells towards a cell type with neuronal and neuroglial cellular morphology.展开更多
Cerebellar ataxias are characterized by a progressive decline in motor coordination,but the specific output circuits and underlying pathological mechanism remain poorly understood.Through cell-type-specific manipulati...Cerebellar ataxias are characterized by a progressive decline in motor coordination,but the specific output circuits and underlying pathological mechanism remain poorly understood.Through cell-type-specific manipulations,we discovered a novel GABAergic Purkinje cell(PC)circuit in the cerebellar IV/V lobe that projected to CaMKIIα+neurons in the fastigial nucleus(FN),which regulated sensorimotor coordination.Furthermore,transcriptomics profiling analysis revealed various cerebellar neuronal identities,and we validated that biorientation defective 1(BOD1)played an important role in the circuit of IV/V lobe to FN.BOD1 deficit in PCs of IV/V lobe attenuated the excitability and spine density of PCs,accompany with ataxia behaviors.Instead,BOD1 enrichment in PCs of IV/V lobe reversed the hyperexcitability of CaMKIIα+neurons in the FN and ameliorated ataxia behaviors in L7-Cre;BOD1f/f mice.Together,these findings further suggest that specific regulation of the cerebellar IV/V lobePCs→FNCaMKIIα+circuit might provide neuromodulatory targets for the treatment of ataxia behaviors.展开更多
Stimulation of cerebellar interpositus nucleus and (astigial nucleus could influence the neuronal activi-ty of lateral hypothalamic area in the cat, and some of the neurons which respond to the cerebellar stimulations...Stimulation of cerebellar interpositus nucleus and (astigial nucleus could influence the neuronal activi-ty of lateral hypothalamic area in the cat, and some of the neurons which respond to the cerebellar stimulations are glucose-sensitive neurons. These results suggest that the cerebellum is involved not only in motor control, but also in the regulation of non-somatic functions through the cerebello-hypothalamic pathways.展开更多
The effects of stimulating locus coeruleus (LC) on neuronal activity of cerebellar fastigial nucleus (FN) was investigated. Stimulation of LC elicited inhibitory, excitatory and biphasic (inhibition-excitation) respon...The effects of stimulating locus coeruleus (LC) on neuronal activity of cerebellar fastigial nucleus (FN) was investigated. Stimulation of LC elicited inhibitory, excitatory and biphasic (inhibition-excitation) responses from FN cells. The majority of responsive cells showed an inhibitory response with a latency of less than 10 ms. Injection of α adrenoreceptor antagonists phentolamine (ⅳ) could block the inhibitory response of FN cells to the LC stimulation, but propranolol (ⅳ), a β adrenoreceptor antagonist, could not. These results suggest that LC-cerebellar noradrenergic afferent fibers may be involved in the cerebellar sensorimotor integration process by exerting their modulatory action on the cerebellar nuclear cells’ activities.展开更多
基金Key Technologies Research and Development Program of Chongqing Municipal Science Committee, No.2003-7Scientific Research Project of Health Bureau of Chongqing City,No.2005-2-179
文摘BACKGROUND： Previous studies have confirmed that fastigial nucleus electrical stimulation can induce endogenous neuroprotective mechanisms and produce wide and long-lasting neuroprotective effects. Nevertheless, the precise mechanisms remain poorly understood. OBJECTIVE： This study was designed to observe the effects of fastigial nucleus electrical stimulation on nestin-positive cell expression in adult rat lateral ventricle after focal cerebral ischemia/reperfusion, as well as neurological functional changes as a function of time. DESIGN： A randomized controlled animal experiment. SETTING： Department of Neurology, First Affiliated Hospital of Chongqing Medical University; Chongqing Key Laboratory of Neurology. MATERIALS： This study was performed in the Department of Neurology, First Affiliated Hospital of Chongqing Medical University and Chongqing Key Laboratory of Neurology from September 2004 to February 2006. A total of 180 healthy, adult, male Wistar rats, aged 8 weeks old, were provided by the Laboratory Animal Center of Chongqing Medical University. The main reagents and equipments were as follows： rabbit anti-rat nestin monoclonal antibody （Wuhan Boster Company, China）. METHODS： The included male Wistar rats were randomly divided into 5 groups： normal control, sham-operated, model, fastigial nucleus sham-stimulation （sham-stimulation for short）, and fastigial nucleus electrical stimulation （stimulation for short） groups. Six time points （1 hour of ischemia and 1, 3, 7, 14, 21, and 28 days of reperfusion, 6 rats per time point） were allotted to each group. Cerebral ischemia/reperfusion was performed by occlusion to the right middle cerebral artery with suture, followed by suture removal. In the stimulation group, subsequent to reperfusion, the rat left cerebellar fastigial nucleus was immediately subjected to 1 hour of stimulation. After anesthesia, the rat left cerebellar fastigial nucleus was stimulated for 1 hour using a square-wave electronic stimulator with a current intensity of 50 μ A, frequency of 50-100 Hz, and duration of 0.5 ms. In the sham-stimulation group, the procedure was identical to the stimulation group, except the needle was retained for 1 hour and current stimulation was withdrawn. In the model group, rats were subjected to cerebral ischemia/reperfusion, but electrical stimulation was omitted. In the sham-operated group, the internal carotid artery, rather than the middle cerebral artery, was inserted with suture, and simultaneously, electrical stimulation was omitted. In the normal control group, the rats received no treatments. MAIN OUTCOME MEASURES： Nestin-positive cells were detected by immunohistochemical staining in the rat ischemic lateral cerebral ventricle at 1, 3, 7, 14, 21, and 28 days post-reperfusion. RESULTS： Morphological changes of nestin-positive cells in the ischemic lateral ventricle： in the normal control group, very few nestin-positive cells were detected in the choroid plexus, ependyma, and subependymal region of the lateral ventricle. In the model group, the number of nestin-positive cells exhibited a tendency towards a single peak, i.e., cells increased at day 1, reached peak levels by day 7, and then decreased sharply. Fastigial nucleus electrical stimulation was administered following focal cerebral ischemia/reperfusion, and results revealed that nestin-positive cell morphology was similar to horizontal cell morphology on day 7. The number of nestin-positive cells decreased after 14 days; however, the proportion of horizontal cell-like cells increased. In the sham-stimulation group, there was no change in nestin-positive cells, nestin-positive cell expression in the ischemic lateral ventricle： nestin-positive cell expression increased in the ischemic lateral cerebral ventricle, exhibiting a tendency towards unimodality; the number of cells peaked on day 7 （P 〈 0.01） and gradually decreased after 14 days （P 〈 0.01）. Following fastigial nucleus electrical stimulation, the number of nestin-positive cells increased significantly （P 〈 0.05-0.01）, reached peak levels by day 7 （P 〈 0.01）, and remained at very high levels after 14 days （P 〈 0.01）. Neurofunctional changes： neurofunctional deficits were gradually alleviated with prolonged focal cerebral ischemia/reperfusion time. At 1 hour of ischemia, and 6 hours to 7 days of reperfusion, rat neurological scores were significantly lower in the stimulation group than in the model and sham-operation groups （P 〈 0.05-0.01）. CONCLUSION： Fastigial nucleus electrical stimulation increased nestin-positive cells in the rat lateral ventricle after focal cerebral ischemia/reperfusion in a time-dependent manner and simultaneously improved neurological deficits, as well as promoted differentiation of nestin-positive cells towards a cell type with neuronal and neuroglial cellular morphology.
基金funded by the National Natural Science Foundations of China(grant no.81973300 to YML,grant no.82104162 to X.X.L.and grant no.81803506 to Q.J.)the State Key Program of National Natural Science Foundations of China(grant no.81930103 to F.H.).
文摘Cerebellar ataxias are characterized by a progressive decline in motor coordination,but the specific output circuits and underlying pathological mechanism remain poorly understood.Through cell-type-specific manipulations,we discovered a novel GABAergic Purkinje cell(PC)circuit in the cerebellar IV/V lobe that projected to CaMKIIα+neurons in the fastigial nucleus(FN),which regulated sensorimotor coordination.Furthermore,transcriptomics profiling analysis revealed various cerebellar neuronal identities,and we validated that biorientation defective 1(BOD1)played an important role in the circuit of IV/V lobe to FN.BOD1 deficit in PCs of IV/V lobe attenuated the excitability and spine density of PCs,accompany with ataxia behaviors.Instead,BOD1 enrichment in PCs of IV/V lobe reversed the hyperexcitability of CaMKIIα+neurons in the FN and ameliorated ataxia behaviors in L7-Cre;BOD1f/f mice.Together,these findings further suggest that specific regulation of the cerebellar IV/V lobePCs→FNCaMKIIα+circuit might provide neuromodulatory targets for the treatment of ataxia behaviors.
基金Project supported by the National Natural Science Foundation of China, a FEYUT grant and a grant from the State Education Commission of China in aid of scholars returning from overseas.
文摘Stimulation of cerebellar interpositus nucleus and (astigial nucleus could influence the neuronal activi-ty of lateral hypothalamic area in the cat, and some of the neurons which respond to the cerebellar stimulations are glucose-sensitive neurons. These results suggest that the cerebellum is involved not only in motor control, but also in the regulation of non-somatic functions through the cerebello-hypothalamic pathways.
文摘The effects of stimulating locus coeruleus (LC) on neuronal activity of cerebellar fastigial nucleus (FN) was investigated. Stimulation of LC elicited inhibitory, excitatory and biphasic (inhibition-excitation) responses from FN cells. The majority of responsive cells showed an inhibitory response with a latency of less than 10 ms. Injection of α adrenoreceptor antagonists phentolamine (ⅳ) could block the inhibitory response of FN cells to the LC stimulation, but propranolol (ⅳ), a β adrenoreceptor antagonist, could not. These results suggest that LC-cerebellar noradrenergic afferent fibers may be involved in the cerebellar sensorimotor integration process by exerting their modulatory action on the cerebellar nuclear cells’ activities.
