Somatostatin-Positive Neurons in the Rostral Zona Incerta Modulate Innate Fear-Induced Defensive Response in Mice / 神经科学通报·英文版

Defensive behaviors induced by innate fear or Pavlovian fear conditioning are crucial for animals to avoid threats and ensure survival. The zona incerta (ZI) has been demonstrated to play important roles in fear learning and fear memory, as well as modulating auditory-induced innate defensive behavior. However, whether the neuronal subtypes in the ZI and specific circuits can mediate the innate fear response is largely unknown. Here, we found that somatostatin (SST)-positive neurons in the rostral ZI of mice were activated by a visual innate fear stimulus. Optogenetic inhibition of SST-positive neurons in the rostral ZI resulted in reduced flight responses to an overhead looming stimulus. Optogenetic activation of SST-positive neurons in the rostral ZI induced fear-like defensive behavior including increased immobility and bradycardia. In addition, we demonstrated that manipulation of the GABAergic projections from SST-positive neurons in the rostral ZI to the downstream nucleus reuniens (Re) mediated fear-like defensive behavior. Retrograde trans-synaptic tracing also revealed looming stimulus-activated neurons in the superior colliculus (SC) that projected to the Re-projecting SST-positive neurons in the rostral ZI (SC-ZIrSST-Re pathway). Together, our study elucidates the function of SST-positive neurons in the rostral ZI and the SC-ZIrSST-Re tri-synaptic circuit in mediating the innate fear response.

Glutamatergic Neurons in the Caudal Zona Incerta Regulate Parkinsonian Motor Symptoms in Mice / 神经科学通报·英文版

Parkinson's disease (PD) is the second most common and fastest-growing neurodegenerative disorder. In recent years, it has been recognized that neurotransmitters other than dopamine and neuronal systems outside the basal ganglia are also related to PD pathogenesis. However, little is known about whether and how the caudal zona incerta (ZIc) regulates parkinsonian motor symptoms. Here, we showed that specific glutamatergic but not GABAergic ZIc

Treatment of Hemichoreoathetosis with Arrhythmic Proximal Tremor after Stroke: The Role of Zona Incerta as a Target for Deep Brain Stimulation

Deep brain stimulation (DBS) of the zona incerta has shown promising results in the reduction of medically refractory movement disorders. However, evidence supporting its efficacy in movement disorders secondary to hemorrhagic stroke or hemichoreoathetosis is limited. We describe a 48-year-old man who developed progressive hemichoreoathetosis with an arrhythmic, proximal tremor in his right arm following a thalamic hemorrhagic stroke. Pharmacological treatment was carried out with no change in the Abnormal Involuntary Movement Scale (AIMS) score after 4 weeks (14). After six sessions of botulinum toxin treatment, a subtle improvement in the AIMS score (13) was registered, but no clinical improvement was noted. The arrhythmic proximal movements were significantly improved after DBS of the zona incerta with a major decrease in the patient’s AIMS score (8). The response to DBS occurring after the failure of pharmacological and botulinum toxin treatments suggests that zona incerta DBS may be an alternative for postthalamic hemorrhage movement disorders.

Effects of γ-aminobutyric acid on feeding changes in rats and its potential mechanism / 中华行为医学与脑科学杂志

Objective To investigate whether γ-aminobutyric acid (GABA) receptor signaling pathway is involved in the regulation of thalamic undefined (ZI)-nucleus accumbens (NAc) neural pathways on gastric distraction (GD)-sensitive neuronal firing activity and the impact on food intake,the number of times and the frequency in rats.Methods Six rats were randomly selected and the neural pathway between Zl and NAc in rat thalamus was observed by fluorescent gold (FG) retrograde tracing method.Eighty-two rats were randomly selected,and the gastric balloon was placed in gastric cavity,the microelectrode was placed in the NAc,and the stimulating electrode was placed in the ZI.The single-cell discharge recording method was used to observe the effect of electrical stimulation ZI on the excitability of GD-sensitive neurons in rat NAc.Eighteen rats were randomly selected and were divided into three groups according to the random number table.They were NS group,GABA group,GABA + GABA receptor antagonist bicuculline (BIC) group with 6 in each group,and the rat NAc was used to embed the cannula.The method of GABA and BIC was injected to observe the changes of cumulative food intake in rats for 4 h.Eighteen rats were randomly selected and randomly divided into three groups:sham stimulation (SS) group,50 μA electrical stimulation group,50 μA electrical stimulation + BIC group with 6 in each group.The 4 h cumulative food intake of rats was observed by electro-stimulation of rat ZI and rat NAc injection of BIC.Results Fluorescent gold retrograde tracking combined with fluorescent immunohistochemical staining showed that there were visible GABA and fluorescent gold double labeled neurons in ZI.Electrical stimulation of ZI,the frequency of GABA-sensitive GD neurons in rat NAc increased significantly (GD-E increase:(78.8±8.4) ％,GD-I increase:(89.3±9.2) ％,P＜0.01),but the inhibitory effect was antagonized by BIC (GD-E increase:(113.8 ± 13.6)％,GD-I increase:(121.8± 14.2)％,P＜0.01).Microinjection of GABA in rat NAc significantly increased the cumulative food intake for 4 h ((155.72± 18.84) kcal,t=3.41,P＜0.05),which was antagonized by partial BIC (123.43± 15.11) kcal,t =3.28,P＜ 0.05).Electrical stimulation of ZI significantly increased the food intake in rats ((39.07± 11.27) kcal,t =2.96,P＜0.05),and this effect can be partially antagonized by BIC ((34.17 ± 10.85) kcal,t =2.33,P＜ 0.05).Conclusion The ZI-NAc neural pathway regulates the discharge activity of rat gastric distension (GD)-sensitive neurons and the feeding status of rats,and the GABA receptor signaling pathway may be involved in mediating the process.

Effects of γ-aminobutyric acid on feeding changes in rats and its potential mechanism / 中华行为医学与脑科学杂志

Objective@#To investigate whether γ-aminobutyric acid (GABA) receptor signaling pathway is involved in the regulation of thalamic undefined (ZI)-nucleus accumbens (NAc) neural pathways on gastric distraction (GD)-sensitive neuronal firing activity and the impact on food intake, the number of times and the frequency in rats.@*Methods@#Six rats were randomly selected and the neural pathway between ZI and NAc in rat thalamus was observed by fluorescent gold (FG) retrograde tracing method.Eighty-two rats were randomly selected, and the gastric balloon was placed in gastric cavity, the microelectrode was placed in the NAc, and the stimulating electrode was placed in the ZI. The single-cell discharge recording method was used to observe the effect of electrical stimulation ZI on the excitability of GD-sensitive neurons in rat NAc.Eighteen rats were randomly selected and were divided into three groups according to the random number table. They were NS group, GABA group, GABA + GABA receptor antagonist bicuculline (BIC) group with 6 in each group, and the rat NAc was used to embed the cannula. The method of GABA and BIC was injected to observe the changes of cumulative food intake in rats for 4 h. Eighteen rats were randomly selected and randomly divided into three groups: sham stimulation (SS) group, 50 μA electrical stimulation group, 50 μA electrical stimulation + BIC group with 6 in each group. The 4 h cumulative food intake of rats was observed by electro-stimulation of rat ZI and rat NAc injection of BIC.@*Results@#Fluorescent gold retrograde tracking combined with fluorescent immunohistochemical staining showed that there were visible GABA and fluorescent gold double labeled neurons in ZI. Electrical stimulation of ZI, the frequency of GABA-sensitive GD neurons in rat NAc increased significantly (GD-E increase: (78.8±8.4)%, GD-I increase: (89.3±9.2)%, P<0.01), but the inhibitory effect was antagonized by BIC (GD-E increase: (113.8±13.6)%, GD-I increase: (121.8±14.2)%, P<0.01). Microinjection of GABA in rat NAc significantly increased the cumulative food intake for 4 h ((155.72±18.84) kcal, t=3.41, P<0.05), which was antagonized by partial BIC (123.43±15.11) kcal, t=3.28, P<0.05). Electrical stimulation of ZI significantly increased the food intake in rats ((39.07±11.27) kcal, t=2.96, P<0.05), and this effect can be partially antagonized by BIC ((34.17±10.85)kcal, t=2.33, P<0.05).@*Conclusion@#The ZI-NAc neural pathway regulates the discharge activity of rat gastric distension (GD)-sensitive neurons and the feeding status of rats, and the GABA receptor signaling pathway may be involved in mediating the process.