1
|
Effects of ketamine on voltage-gated sodium channels in the barrel cortex and the ventral posteromedial nucleus slices of rats. Neuroreport 2020; 30:1197-1204. [PMID: 31568204 PMCID: PMC6855387 DOI: 10.1097/wnr.0000000000001344] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Ketamine is commonly used as a dissociative anesthetic with unique actions in the central nervous system. Previous studies have found that the thalamocortical systems play an important role in general anesthetics induced unconsciousness. Whether the voltage-gated sodium channels in the thalamocortical systems are the target of ketamine remain unclear. The present study used a whole-cell patch-clamp technique to observe the effects of ketamine on voltage-gated Na channels in thalamocortical pyramidal neurons. We found that IC50 of ketamine on Na currents in the primary somatosensory barrel cortex pyramidal neurons and the thalamus ventral posteromedial nucleus pyramidal neurons was 686.72 ± 39.92 and 842.65 ± 87.28 μM, respectively. Ketamine accelerated the Na channels inactivation and slowed inactivation of Na channels after recovery but did not affect the activation. We demonstrated the detailed suppression process of neural voltage-gated Na channels by ketamine on thalamocortical slice. This may provide a new insight into the mechanical explanation for the ketamine anesthesia.
Collapse
|
2
|
Xiong J, Wang H, Bao Y, Guo Y, Sun Y. Electric vagal nerve stimulation inhibits inflammation and improves early postoperation cognitive dysfunction in aged rats. BMC Anesthesiol 2019; 19:217. [PMID: 31759387 PMCID: PMC6875068 DOI: 10.1186/s12871-019-0885-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2019] [Accepted: 11/05/2019] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND This study aimed to evaluate effects of electric vagal nerve stimulation on early postoperation cognitive dysfunction in aged rats. METHODS A total of 33 male Sprague Dawley rats were selected and assigned randomly to three groups, control group (C, n = 10), splenectomy group (S, n = 10) and splenectomy+vagal nerve stimulation group (SV, n = 13). Behavior and memory of rats were evaluated by Open Field Test and Morris Water Maze. Levels of TNF-α, IL-6 and IL-10 in serum were measured by ELISA. The level of TNF-α protein in hippocampus was assessed by Western blotting. rt-PCR was used to detect mRNA expression of NF-κB in hippocampus. RESULTS During anesthesia/operation, vital life signs of rats were stable. In SV group, vagal nerve stimulation decreased heart rate lower than 10% of basic level and kept it at a stable range by regulating stimulation intensity. After stimulation stop, heart rate returned to the basic level again. This indicated that the model of vagal nerve stimulation was successful. Serum levels of TNF-α and IL-6 increased by the operation/anesthesia, but they decreased with vagal nerve stimulation (all P < 0.05). TNF-α protein and mRNA expression of NF-κB in hippocampus were also eliminated by vagal nerve stimulation compared to S group (P < 0.05). Results of Morris Water Maze showed escape latency of postoperation in S group was significantly longer than C group (P < 0.05), and times of crossing platform in S group was lower than that of C group (P < 0.05). Although escape latency of postopration in SV group was shorter than that of S group, there was no significant difference between two groups. Meanwhile there were no significant differences of behavior test in Open Field test between three groups, although vagal nerve stimulation improved partly active explore behavior compared to S group. CONCLUSION The inflammation caused by operation and general anesthesia was an important reason of early postoperation cognitive dysfunction, and electric vagal nerve stimulation could inhibit the inflammation. Meanwhile, vagal nerve stimulation could ameliorate early postoperation cognitive dysfunction partly, but its protective effects were not enough and should be studied and improved in future.
Collapse
Affiliation(s)
- Jun Xiong
- Department of Anesthesiology, Sanbo Brain Hospital, Capital Medical University, No. 50 Yikesong, Xiangshan, Haidian District, Beijing, 100093, China
| | - Huijun Wang
- Department of Anesthesiology, Tongren Hospital, Capital Medical University, No. 1 Dongjiao Minxiang, Dongcheng District, Beijing, 100730, China
| | - Yin Bao
- Department of Anesthesiology, Tongren Hospital, Capital Medical University, No. 1 Dongjiao Minxiang, Dongcheng District, Beijing, 100730, China
| | - Yuliang Guo
- Department of Anesthesiology, Tongren Hospital, Capital Medical University, No. 1 Dongjiao Minxiang, Dongcheng District, Beijing, 100730, China
| | - Yongxing Sun
- Department of Anesthesiology, Sanbo Brain Hospital, Capital Medical University, No. 50 Yikesong, Xiangshan, Haidian District, Beijing, 100093, China.
| |
Collapse
|
3
|
Fu B, Liu C, Zhang Y, Fu X, Zhang L, Yu T. Ketamine attenuates the glutamatergic neurotransmission in the ventral posteromedial nucleus slices of rats. BMC Anesthesiol 2017; 17:111. [PMID: 28835217 PMCID: PMC5569565 DOI: 10.1186/s12871-017-0404-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2017] [Accepted: 08/16/2017] [Indexed: 01/15/2023] Open
Abstract
Background Ketamine is a frequently used intravenous anesthetic, which can reversibly induce loss of consciousness (LOC). Previous studies have demonstrated that thalamocortical system is critical for information transmission and integration in the brain. The ventral posteromedial nucleus (VPM) is a critical component of thalamocortical system. Glutamate is an important excitatory neurotransmitter in the brain and may be involved in ketamine-induced LOC. Methods The study used whole-cell patch-clamp to observe the effect of ketamine (30 μM–1000 μM) on glutamatergic neurotransmission in VPM slices. Results Ketamine significantly decreased the amplitude of glutamatergic spontaneous excitatory postsynaptic currents (sEPSCs), but only higher concentration of ketamine (300 μM and 1000 μM) suppressed the frequency of sEPSCs. Ketamine (100 μM–1000 μM) also decreased the amplitude of glutamatergic miniature excitatory postsynaptic currents (mEPSCs), without altering the frequency. Conclusions In VPM neurons, ketamine attenuates the glutamatergic neurotransmission mainly through postsynaptic mechanism and action potential may be involved in the process. Electronic supplementary material The online version of this article (doi:10.1186/s12871-017-0404-5) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Bao Fu
- Department of Critical Care Medicine, Affiliated Hospital of Zunyi Medical College, Zunyi, Guizhou, China
| | - Chengxi Liu
- Guizhou Key Laboratory of Anesthesia and Organ Protection, Zunyi Medical College, Dalian Road, Zunyi, Guizhou, 201, China
| | - Yajun Zhang
- Guizhou Key Laboratory of Anesthesia and Organ Protection, Zunyi Medical College, Dalian Road, Zunyi, Guizhou, 201, China
| | - Xiaoyun Fu
- Department of Critical Care Medicine, Affiliated Hospital of Zunyi Medical College, Zunyi, Guizhou, China
| | - Lin Zhang
- Guizhou Key Laboratory of Anesthesia and Organ Protection, Zunyi Medical College, Dalian Road, Zunyi, Guizhou, 201, China
| | - Tian Yu
- Guizhou Key Laboratory of Anesthesia and Organ Protection, Zunyi Medical College, Dalian Road, Zunyi, Guizhou, 201, China.
| |
Collapse
|
4
|
Propofol enhances facial stimulation-evoked responses in the cerebellar granule cell layer via NMDA receptor activation in mice in vivo. Eur J Pharmacol 2016; 788:37-44. [DOI: 10.1016/j.ejphar.2016.05.027] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2016] [Accepted: 05/23/2016] [Indexed: 11/20/2022]
|
5
|
Fu B, Wang Y, Yang H, Yu T. Effects of Etomidate on GABAergic and Glutamatergic Transmission in Rat Thalamocortical Slices. Neurochem Res 2016; 41:3181-3191. [PMID: 27561291 DOI: 10.1007/s11064-016-2042-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2016] [Revised: 08/10/2016] [Accepted: 08/22/2016] [Indexed: 12/14/2022]
Abstract
Although accumulative evidence indicates that the thalamocortical system is an important target for general anesthetics, the underlying mechanisms of anesthetic action on thalamocortical neurotransmission are not fully understood. The aim of the study is to explore the action of etomidate on glutamatergic and GABAergic transmission in rat thalamocortical slices by using whole cell patch-clamp recording. We found that etomidate mainly prolonged the decay time of spontaneous GABAergic inhibitory postsynaptic currents (sIPSCs), without changing the frequency. Furthermore, etomidate not only prolonged the decay time of miniature inhibitory postsynaptic currents (mIPSCs) but also increased the amplitude. On the other hand, etomidate significantly decreased the frequency of spontaneous glutamatergic excitatory postsynaptic currents (sEPSCs), without altering the amplitude or decay time in the absence of bicuculline. When GABAA receptors were blocked using bicuculline, the effects of etomidate on sEPSCs were mostly eliminated. These results suggest that etomidate enhances GABAergic transmission mainly through postsynaptic mechanism in thalamocortical neuronal network. Etomidate attenuates glutamatergic transmission predominantly through presynaptic action and requires presynaptic GABAA receptors involvement.
Collapse
Affiliation(s)
- Bao Fu
- Department of Critical Care Medicine, Affiliated Hospital of Zunyi Medical College, Zunyi, Guizhou, China
| | - Yuan Wang
- Department of Anesthesiology, Affiliated Hospital of Zunyi Medical College, Zunyi, Guizhou, China
| | - Hao Yang
- Guizhou Key Laboratory of Anesthesia and Organ Protection, Zunyi Medical College, Dalian road 149, Zunyi, 563000, Guizhou, China
| | - Tian Yu
- Guizhou Key Laboratory of Anesthesia and Organ Protection, Zunyi Medical College, Dalian road 149, Zunyi, 563000, Guizhou, China.
| |
Collapse
|
6
|
Effects of Ketamine on Neuronal Spontaneous Excitatory Postsynaptic Currents and Miniature Excitatory Postsynaptic Currents in the Somatosensory Cortex of Rats. IRANIAN JOURNAL OF MEDICAL SCIENCES 2016; 41:275-82. [PMID: 27365548 PMCID: PMC4912645] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Ketamine is a commonly used intravenous anesthetic which produces dissociation anesthesia, analgesia, and amnesia. The mechanism of ketamine-induced synaptic inhibition in high-level cortical areas is still unknown. We aimed to elucidate the effects of different concentrations of ketamine on the glutamatergic synaptic transmission of the neurons in the primary somatosensory cortex by using the whole-cell patch-clamp method. METHODS Sprague-Dawley rats (11-19 postnatal days, n=36) were used to obtain brain slices (300 μM). Spontaneous excitatory postsynaptic currents (data from 40 neurons) were recorded at a command potential of -70 mV in the presence of bicuculline (a competitive antagonist of GABAA receptors, 30 μM) and strychnine (glycine receptor antagonist, 30 μM). Miniature excitatory postsynaptic currents (data from 40 neurons) were also recorded when 1 μM of tetrodotoxin was added into the artificial cerebrospinal fluid. We used GraphPad Prism5for statistical analysis. Significant differences in the mean amplitude and frequency were tested using the Student paired 2-tailed t test. Values of P<0.05 were considered significant. RESULTS Different concentrations of ketamine inhibited the frequency and amplitude of the spontaneous excitatory postsynaptic currents as well as the amplitude of the miniature excitatory postsynaptic currents in a concentration-dependent manner, but they exerted no significant effect on the frequency of the miniature excitatory postsynaptic currents. CONCLUSION Ketamine inhibited the excitatory synaptic transmission of the neurons in the primary somatosensory cortex. The inhibition may have been mediated by a reduction in the sensitivity of the postsynaptic glutamatergic receptors.
Collapse
|
7
|
Huang C, Ng OTW, Ho YS, Irwin MG, Chang RCC, Wong GTC. Effect of Continuous Propofol Infusion in Rat on Tau Phosphorylation with or without Temperature Control. J Alzheimers Dis 2016; 51:213-26. [PMID: 26836157 DOI: 10.3233/jad-150645] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Several studies suggest a relationship between anesthesia-induced tau hyperphosphorylation and the development of postoperative cognitive dysfunction. This study further characterized the effects of continuous propofol infusion on tau protein phosphorylation in rats, with or without temperature control. Propofol was administered intravenously to 8-10-week-old male Sprague-Dawley rats and infused to the loss of the righting reflex for 2 h continuously. Proteins from cortex and hippocampus were examined by western blot and immunohistochemistry. Rectal temperature was significantly decreased during propofol infusion. Propofol with hypothermia significantly increased phosphorylation of tau at AT8, AT180, Thr205, and Ser199 in cortex and hippocampus except Ser396. With temperature maintenance, propofol still induced significant elevation of AT8, Thr205, and Ser199 in cortex and hippocampus; however, increase of AT180 and Ser396 was only found in hippocampus and cortex, respectively. Differential effects of propofol with or without hypothermia on multiple tau related kinases, such as Akt/GSK3β, MAPK pathways, or phosphatase (PP2A), were demonstrated in region-specific manner. These findings indicated that propofol increased tau phosphorylation under both normothermic and hypothermic conditions, and temperature control could partially attenuate the hyperphosphorylation of tau. Further studies are warranted to determine the long-term impact of propofol on the tau pathology and cognitive functions.
Collapse
Affiliation(s)
- Chunxia Huang
- Department of Anaesthesiology, LKS Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
- Laboratory of Neurodegenerative Diseases, School of Biomedical Sciences, LKS Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
| | - Olivia Tsz-Wa Ng
- Laboratory of Neurodegenerative Diseases, School of Biomedical Sciences, LKS Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
- State Key Laboratory of Brain and Cognitive Sciences, The University of Hong Kong, Hong Kong SAR, China
| | - Yuen-Shan Ho
- School of Nursing, Faculty of Health and Social Sciences, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong SAR, China
| | - Michael Garnet Irwin
- Department of Anaesthesiology, LKS Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
- Research Centre of Heart, Brain, Hormone and Healthy Aging, LKS Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
| | - Raymond Chuen-Chung Chang
- Laboratory of Neurodegenerative Diseases, School of Biomedical Sciences, LKS Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
- Research Centre of Heart, Brain, Hormone and Healthy Aging, LKS Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
- State Key Laboratory of Brain and Cognitive Sciences, The University of Hong Kong, Hong Kong SAR, China
| | - Gordon Tin-Chun Wong
- Department of Anaesthesiology, LKS Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
- Research Centre of Heart, Brain, Hormone and Healthy Aging, LKS Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
| |
Collapse
|
8
|
Propofol facilitates excitatory inputs of cerebellar Purkinje cells by depressing molecular layer interneuron activity during sensory information processing in vivo in mice. Neuroreport 2015; 26:921-7. [DOI: 10.1097/wnr.0000000000000449] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|