Activation of GABAergic neurons in the zona incerta accelerates anesthesia induction with sevoflurane and propofol without affecting anesthesia maintenance or awakening in mice / 南方医科大学学报

OBJECTIVE@#To explore the regulatory effects of GABAergic neurons in the zona incerta (ZI) on sevoflurane and propofol anesthesia.@*METHODS@#Forty-eight male C57BL/6J mice divided into 8 groups (n=6) were used in this study. In the study of sevoflurane anesthesia, chemogenetic experiment was performed in 2 groups of mice with injection of either adeno-associated virus carrying hM3Dq (hM3Dq group) or a virus carrying only mCherry (mCherry group). The optogenetic experiment was performed in another two groups of mice injected with an adeno-associated virus carrying ChR2 (ChR2 group) or GFP only (GFP group). The same experiments were also performed in mice for studying propofol anesthesia. Chemogenetics or optogenetics were used to induce the activation of GABAergic neurons in the ZI, and their regulatory effects on anesthesia induction and arousal with sevoflurane and propofol were observed; EEG monitoring was used to observe the changes in sevoflurane anesthesia maintenance after activation of the GABAergic neurons.@*RESULTS@#In sevoflurane anesthesia, the induction time of anesthesia was significantly shorter in hM3Dq group than in mCherry group (P < 0.05), and also shorter in ChR2 group than in GFP group (P < 0.01), but no significant difference was found in the awakening time between the two groups in either chemogenetic or optogenetic tests. Similar results were observed in chemogenetic and optogenetic experiments with propofol (P < 0.05 or 0.01). Photogenetic activation of the GABAergic neurons in the ZI did not cause significant changes in EEG spectrum during sevoflurane anesthesia maintenance.@*CONCLUSION@#Activation of the GABAergic neurons in the ZI promotes anesthesia induction of sevoflurane and propofol but does not affect anesthesia maintenance or awakening.

The changes of neuronal activity of the zone incerta in a rodent model of Parkinson's disease / 西安交通大学学报·英文版

Objective: To study the changes in neuronal activity of the zone incerta (ZI) following the unilateral lesion of the nigrostriatal pathway. Methods: Electrophysiological recordings of ZI neurons were made in normal rats and in two groups of rats at different time intervals after injection of 6-hydrodopamine (6-OHDA) into the pars compacta of substantia nigra by extracellular recording in vivo. Results: The results showed a significant increase in the mean firing rate of ZI during the second and fourth weeks after 6-OHDA lesion [n = 32, (3.6±2) Hz, Plt;0.001; n = 35, (9.3±6.6) Hz, P<0.001, respectively] compared to that of normal rats [n = 39, (9.2±5.2) Hz]. However, no significant change was observed between two groups of 6-OHDA-lesioned rats. With regard to firing pattern, 7.7% (3/39) of ZI neurons discharged regularly, 82.1% (32/39) irregularly and 10.3% (4/39) in bursts in normal rats. During the second week after 6-OHDA lesion, the regular, irregular and bursting firing neurons recorded in the ZI were 9.4% (3/32), 59.4% (19/32) and 31.3% (10/32), and during fourth week, the regular, irregular and bursting firing neurons were 14.3% (5/35) , 57.1% (20/35) and 28.6% (10/35), respectively. The firing pattern of the neurons in the three different groups did not change significantly. Conclusion: These results suggest that the firing rate of ZI neurons in 6-OHDA-lesioned rats is increased significantly, which may contribute to the pathophysiology of Parkinson's disease.

The changes of neuronal activity of the zone incerta in a rodent model of Parkinson's disease / 药物分析学报

Objective To study the changes in neuronal activity of the zone incerta (ZI) following the unilateral lesion of the nigrostriatal pathway. Methods Eiectrophysiological recordings of ZI neurons were made in normal rats and in two groups of rats at different time intervals after injection of 6-hydrodopamine (6-OHDA) into the pars compacta of snbstantia nigra by extracellular recording in vivo. Results The results showed a significant increase in the mean firing rate of ZI during the second and fourth weeks after 6-OHDA lesion [-n=32, (3.6±2. 2)Hz, P<0.001; n=35, (9.3±6.6)Hz, P<0. 001, respectively] compared to that of normal rats [n=39, (9.2±5.2)Hz]. However, no significant change was observed between two groups of 6-OHDA-lesioned rats. With regard to firing pattern, 7.7%(3/39) of ZI neurons discharged regularly, 82.1% (32/39) irregularly and 10. 3% (4/39) in bursts in normal rats. During the second week after 6-OHDA lesion, the regular, irregular and bursting firing neurons recorded in the ZI were 9.4% (3/32), 59. 4% (19/32) and 31.3% (10/32), and during fourth week, the regular, irregular and bursting firing neurons were 14.3% (5/35), 57.1% (20/35) and 28. 6% (10/35), respectively. The firing pattern of the neurons in the three different groups did not change significantly. Conclusion These results suggest that the firing rate of ZI neurons in 6-OHDA-lesioned rats is increased significantly, which may contribute to the pathophysiology of Parkinson's disease.