1
|
Qiu J, Yang Y, Liu J, Zhao W, Li Q, Zhu T, Liang P, Zhou C. The volatile anesthetic isoflurane differentially inhibits voltage-gated sodium channel currents between pyramidal and parvalbumin neurons in the prefrontal cortex. Front Neural Circuits 2023; 17:1185095. [PMID: 37396397 PMCID: PMC10311640 DOI: 10.3389/fncir.2023.1185095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Accepted: 05/25/2023] [Indexed: 07/04/2023] Open
Abstract
Background How volatile anesthetics work remains poorly understood. Modulations of synaptic neurotransmission are the direct cellular mechanisms of volatile anesthetics in the central nervous system. Volatile anesthetics such as isoflurane may reduce neuronal interaction by differentially inhibiting neurotransmission between GABAergic and glutamatergic synapses. Presynaptic voltage-dependent sodium channels (Nav), which are strictly coupled with synaptic vesicle exocytosis, are inhibited by volatile anesthetics and may contribute to the selectivity of isoflurane between GABAergic and glutamatergic synapses. However, it is still unknown how isoflurane at clinical concentrations differentially modulates Nav currents between excitatory and inhibitory neurons at the tissue level. Methods In this study, an electrophysiological recording was applied in cortex slices to investigate the effects of isoflurane on Nav between parvalbumin (PV+) and pyramidal neurons in PV-cre-tdTomato and/or vglut2-cre-tdTomato mice. Results Isoflurane at clinically relevant concentrations produced a hyperpolarizing shift in the voltage-dependent inactivation and slowed the recovery time from the fast inactivation in both cellular subtypes. Since the voltage of half-maximal inactivation was significantly depolarized in PV+ neurons compared to that of pyramidal neurons, isoflurane inhibited the peak Nav currents in pyramidal neurons more potently than those of PV+ neurons (35.95 ± 13.32% vs. 19.24 ± 16.04%, P = 0.036 by the Mann-Whitney test). Conclusions Isoflurane differentially inhibits Nav currents between pyramidal and PV+ neurons in the prefrontal cortex, which may contribute to the preferential suppression of glutamate release over GABA release, resulting in the net depression of excitatory-inhibitory circuits in the prefrontal cortex.
Collapse
Affiliation(s)
- Jingxuan Qiu
- Department of Anesthesiology, West China Hospital of Sichuan University, Chengdu, China
- Laboratory of Anesthesia and Critical Care Medicine, National-Local Joint Engineering Research Centre of Translational Medicine of Anesthesiology, West China Hospital of Sichuan University, Chengdu, China
| | - Yaoxin Yang
- Department of Anesthesiology, West China Hospital of Sichuan University, Chengdu, China
- Laboratory of Anesthesia and Critical Care Medicine, National-Local Joint Engineering Research Centre of Translational Medicine of Anesthesiology, West China Hospital of Sichuan University, Chengdu, China
| | - Jin Liu
- Laboratory of Anesthesia and Critical Care Medicine, National-Local Joint Engineering Research Centre of Translational Medicine of Anesthesiology, West China Hospital of Sichuan University, Chengdu, China
| | - Wenling Zhao
- Department of Anesthesiology, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Qian Li
- Department of Anesthesiology, West China Hospital of Sichuan University, Chengdu, China
- Laboratory of Anesthesia and Critical Care Medicine, National-Local Joint Engineering Research Centre of Translational Medicine of Anesthesiology, West China Hospital of Sichuan University, Chengdu, China
| | - Tao Zhu
- Department of Anesthesiology, West China Hospital of Sichuan University, Chengdu, China
| | - Peng Liang
- Department of Anesthesiology, West China Hospital of Sichuan University, Chengdu, China
| | - Cheng Zhou
- Laboratory of Anesthesia and Critical Care Medicine, National-Local Joint Engineering Research Centre of Translational Medicine of Anesthesiology, West China Hospital of Sichuan University, Chengdu, China
| |
Collapse
|
2
|
Yang H, Zhang Y, Liu C, Ou Y, Zhu Y, Xue Y, Zhao G, Lin Y, Chen C, Xu G, Yuan K, Wang Q, Zhang M, Li L, Liu J, Zhang W. A Multicenter, Randomized, Double-Blind, Positive-Controlled, Non-Inferiority, Phase III Clinical Trial Evaluating the Efficacy and Safety of Emulsified Isoflurane for Anesthesia Induction in Patients. CNS Drugs 2022; 36:1301-1311. [PMID: 36385453 DOI: 10.1007/s40263-022-00970-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 10/13/2022] [Indexed: 11/17/2022]
Abstract
BACKGROUND Emulsified isoflurane was designed to circumvent the deficiencies of inhalation anesthetics, which have a longer time to onset, result in a higher drug consumption, and for which a specific anesthesia machine is required for clinical use. The aim of this study was to compare the efficacy and safety of emulsified isoflurane with propofol for anesthesia induction in adults patients. METHODS This multicenter, randomized, double-blind, positive-controlled, non-inferiority, phase III clinical trial compared the efficacy and safety of emulsified isoflurane with propofol for anesthesia induction. Each patient in the emulsified isoflurane group received a single bolus injection of 12% emulsified isoflurane at a dose of 30 mg/kg, and each patient in the propofol group received a single bolus injection of 0.8% propofol at a dose of 2 mg/kg. The primary outcome of the efficacy evaluation was the proportion of participants with successful anesthesia induction, which was regarded as a Modified Observer's Assessment of Alertness/Sedation (MOAA/S) score of < 1 and lack of use of other sedative drugs. A number of secondary efficacy outcomes were also assessed. Safety was monitored based on (1) adverse events, (2) repeated measurement of vital signs; (3) physical examination, (4) routine laboratory examinations of hematology, biochemistry, urine, coagulation function, and (5) 12-lead electrocardiogram. RESULTS A total of 416 patients were enrolled (n = 208 in each group) and 398 patients were administered study drug. The proportion of participants with successful anesthesia induction was 100% with a 95% confidence interval of - 1.9% to + 1.9% for the emulsified isoflurane and propofol groups, which met the predesigned non-inferiority criteria of 5%. The study demonstrated the non-inferiority of sedation produced by emulsified isoflurane compared to propofol. Among the secondary efficacy outcomes, emulsified isoflurane showed a better cardiovascular stability than propofol. The number of patients from the emulsified isoflurane group who experienced drug-related adverse events was significantly higher than that of patients from the propofol group. However, there was no significant difference between the two groups in terms of adverse events or drug-related adverse events of grades 3-5. CONCLUSIONS Emulsified isoflurane exhibited non-inferiority of anesthesia/sedation compared to propofol in patients undergoing anesthesia induction. CLINICAL TRIAL REGISTRATION ChiCTR2000038185, registered on 12 December, 2020 ( www.chictr.org.cn ).
Collapse
Affiliation(s)
- Hui Yang
- Department of Anesthesiology, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - YuJun Zhang
- Department of Anesthesiology, West China Hospital, Sichuan University, Chengdu, Sichuan, China.,Laboratory of Anaesthesia and Critical Care Medicine, Department of Anesthesiology, National-Local Joint Engineering Research Center of Translational Medicine of Anesthesiology, West China Hospital, Sichuan University, Sichuan, 610041, Chengdu, P. R. China.,National-Local Joint Engineering Research Center of Translational Medicine of Anesthesiology, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - ChuiLiang Liu
- Department of Anesthesiology, Chancheng District Central Hospital of Foshan City, Foshan, Fujian, China
| | - YangWen Ou
- Department of Anesthesiology, The Third Xiangya Hospital of Central South University, Xiangya, Hunan, China
| | - YuHang Zhu
- Department of Anesthesiology, Affiliated Hospital of Zunyi Medical College, Zunyi, Guizhou, China
| | - Yun Xue
- Department of Anesthesiology, Chongqing University Fuling Hospital, Fuling, Chongqing, China
| | - GaoFeng Zhao
- Department of Anesthesiology, Guangdong Provincial Hospital of Traditional Chinese Medicine, Guangzhou, Guangdong, China.,Department of Anesthesiology, Guangdong Hospital of Traditional Chinese Medicine, University City Branch, Guangzhou, Guangdong, China
| | - YuShuang Lin
- Department of Anesthesiology, Zhangzhou Affiliated Hospital of FuJian Medical University, Zhangzhou, Fujian, China
| | - Chun Chen
- Department of Anesthesiology, Yichang Central People's Hospital, Yichang, Hubei, China
| | - GuoHai Xu
- Department of Anesthesiology, The Second Affiliated Hospital of Nanchang University, Nanchang, Jiangxi, China
| | - KaiMing Yuan
- Department of Anesthesiology, The Second Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Qiang Wang
- Department of Anesthesiology, The First Affiliated Hospital of Xi'an Jiaotong University, Xian, Shanxi, China
| | - Min Zhang
- Humanwell Healthcare (Group) Co., Ltd, Yichang, Hubei, China
| | - LiE Li
- Humanwell Healthcare (Group) Co., Ltd, Yichang, Hubei, China
| | - Jin Liu
- Department of Anesthesiology, West China Hospital, Sichuan University, Chengdu, Sichuan, China.,Laboratory of Anaesthesia and Critical Care Medicine, Department of Anesthesiology, National-Local Joint Engineering Research Center of Translational Medicine of Anesthesiology, West China Hospital, Sichuan University, Sichuan, 610041, Chengdu, P. R. China.,National-Local Joint Engineering Research Center of Translational Medicine of Anesthesiology, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - WenSheng Zhang
- Department of Anesthesiology, West China Hospital, Sichuan University, Chengdu, Sichuan, China. .,Laboratory of Anaesthesia and Critical Care Medicine, Department of Anesthesiology, National-Local Joint Engineering Research Center of Translational Medicine of Anesthesiology, West China Hospital, Sichuan University, Sichuan, 610041, Chengdu, P. R. China. .,National-Local Joint Engineering Research Center of Translational Medicine of Anesthesiology, West China Hospital, Sichuan University, Chengdu, Sichuan, China.
| |
Collapse
|
3
|
Yang H, Yin Q, Huang L, Zhang M, Zhang X, Sun Q, Liu X, Wang Q, Yang X, Tan L, Ye M, Liu J. The Bioequivalence of Emulsified Isoflurane With a New Formulation of Emulsion: A Single-Center, Single-Dose, Double-Blinded, Randomized, Two-Period Crossover Study. Front Pharmacol 2021; 12:626307. [PMID: 33776768 PMCID: PMC7988084 DOI: 10.3389/fphar.2021.626307] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Accepted: 01/26/2021] [Indexed: 02/05/2023] Open
Abstract
Background: Emulsified isoflurane is a novel intravenous general anesthetic obtained by encapsulating isoflurane molecules into emulsion. The formulation of emulsion has been improved according to the latest regulations of the China Food and Drug Administration. This study was designed to compare the bioequivalence of the new and previous formulation emulsion of isoflurane. Methods: In a single-center, single-dose, double-blinded, randomized, two-period crossover study, healthy volunteers received intravenous injection of 30 mg/kg of isoflurane with either previous formulation of emulsion isoflurane (PFEI) or new formulation of emulsion isoflurane (NFEI). Arterial and venous blood samples were obtained for geometric mean test/reference ratios of Cmax, AUC0-t, and AUC0-∞, as well as their 90% confidence interval (CI90) as the primary outcome. The secondary outcomes were safety measurements such as vital signs, 12-lead electrocardiography, adverse effects, and laboratory tests; and anesthesia efficacy was assessed by Modified Observer’s Assessment of Alertness/Sedation (MOAA/S) score, bispectral index (BIS), and loss/recovery of eyelash reflex. Results: 24 subjects were eligible, of which 21 completed the whole experiment (NFEI n = 21, PFEI n = 23). Arterial geometric mean test/reference ratios of Cmax, AUC0-t, and AUC0-∞ were 104.50% (CI90 92.81%–117.65%), 108.23% (94.51%–123.96%), and 106.53% (93.94%∼120.80%), respectively. The most commonly seen adverse effects for NFEI and PFEI were injection pain (38.1% vs. 34.8%), hypotension (19.0% vs. 13.0%), apnea (14.3% vs. 17.4%), and upper airway obstruction (14.3% vs. 13.0%). No severe adverse effect was observed. The effectiveness of general anesthesia was similar between the two formulations. Conclusion: The CI90 of Cmax, AUC0-t, AUC0-∞, NFEI, and PFEI were within the range of 80%–125%, suggesting bioequivalence between NFEI and PFEI. The safety and anesthesia effectiveness were also similar.
Collapse
Affiliation(s)
- Hui Yang
- Department of Anesthesiology, West China Hospital, Sichuan University, Chengdu, China
| | - Qinqin Yin
- Department of Anesthesiology, West China Hospital, Sichuan University, Chengdu, China
| | - Luying Huang
- Department of Anesthesiology, West China Hospital, Sichuan University, Chengdu, China.,Department of Clinical Research Management, West China Hospital, Sichuan University, Chengdu, China
| | - Min Zhang
- Clinical Research Center, Yichang Humanwell Pharmaceutical CO., LTD, Yichang, China
| | - Xinxin Zhang
- Clinical Research Center, Yichang Humanwell Pharmaceutical CO., LTD, Yichang, China
| | - Qirong Sun
- Department of Anesthesiology, West China Hospital, Sichuan University, Chengdu, China
| | - Xuewei Liu
- Department of Anesthesiology, West China Hospital, Sichuan University, Chengdu, China
| | - Qi Wang
- Department of Anesthesiology, West China Hospital, Sichuan University, Chengdu, China
| | - Xi Yang
- Department of Anesthesiology, West China Hospital, Sichuan University, Chengdu, China
| | - Lingcan Tan
- Department of Anesthesiology, West China Hospital, Sichuan University, Chengdu, China
| | - Mao Ye
- Department of Anesthesiology, West China Hospital, Sichuan University, Chengdu, China
| | - Jin Liu
- Department of Anesthesiology, West China Hospital, Sichuan University, Chengdu, China
| |
Collapse
|
4
|
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
|
5
|
Hao X, Ou M, Zhang D, Zhao W, Yang Y, Liu J, Yang H, Zhu T, Li Y, Zhou C. The Effects of General Anesthetics on Synaptic Transmission. Curr Neuropharmacol 2020; 18:936-965. [PMID: 32106800 PMCID: PMC7709148 DOI: 10.2174/1570159x18666200227125854] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2019] [Revised: 01/20/2020] [Accepted: 02/26/2020] [Indexed: 02/08/2023] Open
Abstract
General anesthetics are a class of drugs that target the central nervous system and are widely used for various medical procedures. General anesthetics produce many behavioral changes required for clinical intervention, including amnesia, hypnosis, analgesia, and immobility; while they may also induce side effects like respiration and cardiovascular depressions. Understanding the mechanism of general anesthesia is essential for the development of selective general anesthetics which can preserve wanted pharmacological actions and exclude the side effects and underlying neural toxicities. However, the exact mechanism of how general anesthetics work is still elusive. Various molecular targets have been identified as specific targets for general anesthetics. Among these molecular targets, ion channels are the most principal category, including ligand-gated ionotropic receptors like γ-aminobutyric acid, glutamate and acetylcholine receptors, voltage-gated ion channels like voltage-gated sodium channel, calcium channel and potassium channels, and some second massager coupled channels. For neural functions of the central nervous system, synaptic transmission is the main procedure for which information is transmitted between neurons through brain regions, and intact synaptic function is fundamentally important for almost all the nervous functions, including consciousness, memory, and cognition. Therefore, it is important to understand the effects of general anesthetics on synaptic transmission via modulations of specific ion channels and relevant molecular targets, which can lead to the development of safer general anesthetics with selective actions. The present review will summarize the effects of various general anesthetics on synaptic transmissions and plasticity.
Collapse
Affiliation(s)
| | | | | | | | | | | | | | | | - Yu Li
- Address correspondence to these authors at the Laboratory of Anesthesia & Critical Care Medicine, Translational Neuroscience Center, West China Hospital of Sichuan University, Chengdu 610041, Sichuan, P.R. China; E-mail: and Department of Anesthesiology, West China Hospital of Sichuan University, Chengdu, 610041, Sichuan, P.R. China; E-mail:
| | - Cheng Zhou
- Address correspondence to these authors at the Laboratory of Anesthesia & Critical Care Medicine, Translational Neuroscience Center, West China Hospital of Sichuan University, Chengdu 610041, Sichuan, P.R. China; E-mail: and Department of Anesthesiology, West China Hospital of Sichuan University, Chengdu, 610041, Sichuan, P.R. China; E-mail:
| |
Collapse
|
6
|
Ou M, Zhao W, Liu J, Liang P, Huang H, Yu H, Zhu T, Zhou C. The General Anesthetic Isoflurane Bilaterally Modulates Neuronal Excitability. iScience 2019; 23:100760. [PMID: 31926429 PMCID: PMC6956953 DOI: 10.1016/j.isci.2019.100760] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2019] [Revised: 11/16/2019] [Accepted: 12/06/2019] [Indexed: 02/05/2023] Open
Abstract
Volatile anesthetics induce hyperactivity during induction while producing anesthesia at higher concentrations. They also bidirectionally modulate many neuronal functions. However, the neuronal mechanism is unclear. The effects of isoflurane on sodium channel currents were analyzed in acute mouse brain slices, including sodium leak (NALCN) currents and voltage-gated sodium channels (Nav) currents. Isoflurane at sub-anesthetic concentrations increased the spontaneous firing rate of CA3 pyramidal neurons, whereas anesthetic concentrations of isoflurane decreased the firing rate. Isoflurane at sub-anesthetic concentrations enhanced NALCN conductance but minimally inhibited Nav currents. Isoflurane at anesthetic concentrations depressed Nav currents and action potential amplitudes. Isoflurane at sub-anesthetic concentrations depolarized resting membrane potential (RMP) of neurons, whereas hyperpolarized the RMP at anesthetic concentrations. Isoflurane at low concentrations induced hyperactivity in vivo, which was diminished in NALCN knockdown mice. In conclusion, enhancement of NALCN by isoflurane contributes to its bidirectional modulation of neuronal excitability and the hyperactivity during induction. Volatile anesthetic isoflurane exerts bidirectional modulation of neuronal excitability Isoflurane enhances NALCN conductance at sub-anesthetic concentration NALCN knockdown diminishes behavioral hyperactivity during isoflurane induction
Collapse
Affiliation(s)
- Mengchan Ou
- Laboratory of Anesthesia & Critical Care Medicine, Translational Neuroscience Center, West China Hospital of Sichuan University, Chengdu 610041, Sichuan, P.R. China; Department of Anesthesiology, West China Hospital of Sichuan University, Chengdu 610041, Sichuan, P.R. China
| | - Wenling Zhao
- Laboratory of Anesthesia & Critical Care Medicine, Translational Neuroscience Center, West China Hospital of Sichuan University, Chengdu 610041, Sichuan, P.R. China; Department of Anesthesiology, West China Hospital of Sichuan University, Chengdu 610041, Sichuan, P.R. China
| | - Jin Liu
- Laboratory of Anesthesia & Critical Care Medicine, Translational Neuroscience Center, West China Hospital of Sichuan University, Chengdu 610041, Sichuan, P.R. China; Department of Anesthesiology, West China Hospital of Sichuan University, Chengdu 610041, Sichuan, P.R. China
| | - Peng Liang
- Department of Anesthesiology, West China Hospital of Sichuan University, Chengdu 610041, Sichuan, P.R. China
| | - Han Huang
- Department of Anesthesiology, West China Second Hospital of Sichuan University, Chengdu 610041, Sichuan, P.R. China
| | - Hai Yu
- Department of Anesthesiology, West China Hospital of Sichuan University, Chengdu 610041, Sichuan, P.R. China
| | - Tao Zhu
- Department of Anesthesiology, West China Hospital of Sichuan University, Chengdu 610041, Sichuan, P.R. China
| | - Cheng Zhou
- Laboratory of Anesthesia & Critical Care Medicine, Translational Neuroscience Center, West China Hospital of Sichuan University, Chengdu 610041, Sichuan, P.R. China; Department of Anesthesiology, West China Hospital of Sichuan University, Chengdu 610041, Sichuan, P.R. China.
| |
Collapse
|
7
|
Buys M, Scheepers PA, Levin AI. Lipid emulsion therapy: non-nutritive uses of lipid emulsions in anaesthesia and intensive care. SOUTHERN AFRICAN JOURNAL OF ANAESTHESIA AND ANALGESIA 2015. [DOI: 10.1080/22201181.2015.1095470] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
|
8
|
Hyperpolarization-activated cyclic nucleotide-gated channels may contribute to regional anesthetic effects of lidocaine. Anesthesiology 2015; 122:606-18. [PMID: 25485469 DOI: 10.1097/aln.0000000000000557] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
BACKGROUND Local anesthetics (e.g., lidocaine) have been found to inhibit hyperpolarization-activated cyclic nucleotide-gated (HCN) channels besides sodium channels. However, the exact role of HCN channels in regional anesthesia in vivo is still elusive. METHODS Sciatic nerve block and intrathecal anesthesia were performed using lidocaine in wild-type and HCN1 channel knockout (HCN1) mice. EC50 of lidocaine and durations of 1% lidocaine were determined. In electrophysiologic recordings, effects of lidocaine on HCN channel currents, voltage-gated sodium channel currents, and neural membrane properties were recorded on dorsal root ganglia neurons. RESULTS In both sciatic nerve block and intrathecal anesthesia, EC50 of lidocaine for tactile sensory blockade (2 g von Frey fiber) was significantly increased in HCN1 mice, whereas EC50 of lidocaine for pinprick blockade was unaffected. Durations of 1% lidocaine were significantly shorter in HCN1 mice for both sciatic nerve block and intrathecal anesthesia (n = 10). ZD7288 (HCN blocker) could significantly prolong durations of 1% lidocaine including pinprick blockade in sciatic nerve block (n = 10). Forskolin (raising cyclic adenosine monophosphate to enhance HCN2) could significantly shorten duration of pinprick blockade of 1% lidocaine in sciatic nerve block (n = 10). In electrophysiologic recordings, lidocaine could nonselectively inhibit HCN channel and sodium channel currents both in large and in small dorsal root ganglia neurons (n = 5 to 6). Meanwhile, lidocaine caused neural membrane hyperpolarization and increased input resistance of dorsal root ganglia neurons but not in large dorsal root ganglia neurons from HCN1 mice (n = 5-7). CONCLUSIONS These data indicate that HCN channels may contribute to regional anesthetic effects of lidocaine. By inhibiting HCN channels, lidocaine could alter membrane properties of neurons.
Collapse
|
9
|
Hirsch S, Dickenson A, Corradini L. Anesthesia influences neuronal activity and drug effectiveness in neuropathic rats. Pain 2014; 155:2583-2590. [DOI: 10.1016/j.pain.2014.09.021] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2014] [Revised: 09/16/2014] [Accepted: 09/16/2014] [Indexed: 01/16/2023]
|
10
|
Zhou C, Liang P, Liu J, Zhang W, Liao D, Chen Y, Chen X, Li T. Emulsified isoflurane enhances thermal transient receptor potential vanilloid-1 channel activation-mediated sensory/nociceptive blockade by QX-314. Anesthesiology 2014; 121:280-9. [PMID: 24667830 DOI: 10.1097/aln.0000000000000236] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
BACKGROUND QX-314 produces nociceptive blockade, facilitated by permeation through transient receptor potential vanilloid-1 (TRPV1) channels. TRPV1 channel can be activated by noxious heat and sensitized by volatile anesthetics. The authors hypothesized that emulsified isoflurane (EI) could enhance thermal TRPV1 channel activation-mediated sensory/nociceptive blockade by QX-314. METHODS Rats were perineurally injected with QX-314 (Sigma-Aldrich Co. Ltd. Shanghai, China) alone or QX-314 combined with EI, followed by heat exposure on the injection site. The tail-flick and tail-clamping tests were used to assess sensory and nociceptive blockade, respectively; a sciatic nerve block model was used to assess motor and sensory blockade. Effects of EI on thermal activation of TRPV1 channels were evaluated on rat dorsal root ganglia neurons by whole-cell patch-clamp recordings. RESULTS Heat exposure enhanced sensory/nociceptive blockade by QX-314 in rat tails, but not motor blockade in sciatic nerve block model. QX-314 alone or QX-314 + 42°C produced no nociceptive blockade. QX-314 + 48°C produced 100% nociceptive blockade with duration of 12.5 ± 2.0 h (mean ± SEM). By adding 2% EI, QX-314 + 42°C produced 80% nociceptive blockade with duration of 8.1 ± 1.9 h, which was similar to the effect of QX-314 + 46°C (7.7 ± 1.1 h; P = 0.781). The enhancement of heat on sensory/nociceptive blockade of QX-314 was prevented by TRPV1 channel antagonist. The temperature thresholds of TRPV1 channel activation on dorsal root ganglia neurons were significantly reduced by EI. CONCLUSIONS Thermal activation of TRPV1 channels enhanced long-lasting sensory/nociceptive blockade by QX-314 without affecting motor blockade. The addition of EI reduced temperature thresholds for inducing long-lasting sensory/nociceptive blockade due to QX-314.
Collapse
Affiliation(s)
- Cheng Zhou
- From the Laboratory of Anesthesia and Critical Care Medicine (C.Z., J.L., W.Z., D.L., Y.C., X.C., T.L.), Department of Anesthesiology (P.L., J.L., W.Z., X.C.), Translational Neuroscience Center, West China Hospital, Sichuan University, Chengdu, Sichuan, P.R. China
| | | | | | | | | | | | | | | |
Collapse
|
11
|
Zhang Y, He JC, Liu XK, Zhang Y, Wang Y, Yu T. Assessment of the effect of etomidate on voltage-gated sodium channels and action potentials in rat primary sensory cortex pyramidal neurons. Eur J Pharmacol 2014; 736:55-62. [PMID: 24791681 DOI: 10.1016/j.ejphar.2014.04.036] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2013] [Revised: 04/22/2014] [Accepted: 04/23/2014] [Indexed: 11/17/2022]
Abstract
Although it is known that general anesthetics can suppress cortical neurons׳ activity, the underlying mechanisms are still poorly understood, especially the kinetic changes of voltage-gated Na(+) channels, which are mostly related to neuronal excitability. Some general anesthetics have been reported to affect the voltage-gated Na(+) channels in cell culture derived from humans and animals. However no one has ever investigated the effects of etomidate on voltage-gated Na(+) channels in pyramidal neurons using a brain slice. The present study uses a whole cell patch-clamp technique to investigate the changes of voltage-gated Na(+) channels on primary somatosensory cortex pyramidal neurons under the influence of etomidate. We found that etomidate dose-dependently inhibited Na(+) currents of primary somatosensory cortex pyramidal neurons, while shifted the steady-state inactivation curve towards the left and prolonged the recovery time from inactivation. Conversely, etomidate has no effects on the steady-state activation curve. We demonstrated the detailed suppression process of neural voltage-gated Na(+) channels by etomidate on slice condition. This may offer new insights into the mechanical explanation for the etomidate anesthesia. Finding the effects of anesthetics on primary somatosensory cortex also provides evidence to help elucidate the potential mechanism by which tactile information integrates during general anesthesia.
Collapse
Affiliation(s)
- Yu Zhang
- Department of Anesthesiology, Affiliated Hospital of Zunyi Medical College, Zunyi, Guizhou, China; Guizhou Key Laboratory of Anesthesia and Organ Protection, Zunyi Medical College, Zunyi, Guizhou, China
| | - Jiong-ce He
- Department of Anesthesiology, Affiliated Hospital of Zunyi Medical College, Zunyi, Guizhou, China
| | - Xing-kui Liu
- Department of Anesthesiology, Affiliated Hospital of Zunyi Medical College, Zunyi, Guizhou, China
| | - Yi Zhang
- Department of Anesthesiology, Affiliated Hospital of Zunyi Medical College, Zunyi, Guizhou, China
| | - Yuan Wang
- Department of Anesthesiology, Affiliated Hospital of Zunyi Medical College, Zunyi, Guizhou, China
| | - Tian Yu
- Department of Anesthesiology, Affiliated Hospital of Zunyi Medical College, Zunyi, Guizhou, China; Guizhou Key Laboratory of Anesthesia and Organ Protection, Zunyi Medical College, Zunyi, Guizhou, China.
| |
Collapse
|
12
|
Zhou C, Huang H, Liu J, Wang X, Chen X, Zhang W. Emulsified isoflurane increases convulsive thresholds of lidocaine and produces neural protection after convulsion in rats. Anesth Analg 2014; 118:310-317. [PMID: 24445632 DOI: 10.1213/ane.0000000000000065] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
BACKGROUND Local anesthetic-induced convulsions remain a concern of anesthesiologists when performing regional anesthesia. Our previous study found that the lidocaine requirement for IV regional anesthesia was reduced with coadministration of emulsified isoflurane. We designed this study to examine whether emulsified isoflurane could increase the convulsive threshold of lidocaine and produce protection after a lidocaine-induced convulsion. METHODS In experiment 1, the median convulsive dose of lidocaine with or without the addition of emulsified isoflurane was determined using the up-and-down method. In experiment 2, emulsified isoflurane (0.032 mL/kg for isoflurane), midazolam (1.6 mg/kg), 30% Intralipid (solvent of emulsified isoflurane) or saline was infused to treat lidocaine-induced convulsions, respectively. Convulsive behavior was scored by the modified Racine scale. Cognitive function and the pathology of hippocampus cornu ammonis 3 pyramid neurons of rats were evaluated on days 1, 3, 5, and 7 after convulsions. RESULTS In experiment 1, the median convulsive dose of lidocaine alone producing convulsions was 18.7 ± 2.6 mg/kg, and it was increased to 22.7 ± 2.6 (P = 0.010) and 26.7 ± 2.6 mg/kg (P < 0.001) with coadministration of emulsified isoflurane at doses of 0.016 and 0.032 mL/kg isoflurane, respectively. In experiment 2, both emulsified isoflurane and midazolam significantly suppressed lidocaine-induced tonic-clonic seizures. Rats treated with emulsified isoflurane regained full consciousness (convulsive score = 0) significantly earlier than rats treated with midazolam (8.7 ± 2.4 vs 19.5 ± 3.9 minutes, P < 0.001). Cognitive impairment and hippocampus cornu ammonis 3 pyramid neuron abnormalities were found after convulsions and improved with the administration of both emulsified isoflurane and midazolam. CONCLUSION Emulsified isoflurane increased the convulsive threshold of lidocaine and preserved neurological function in rats experiencing lidocaine-induced convulsions.
Collapse
Affiliation(s)
- Cheng Zhou
- From the Laboratory of Anesthesia & Critical Care Medicine, Translational Neuroscience Center, West China Hospital of Sichuan University; Department of Anesthesiology, West China Second Hospital of Sichuan University; and Department of Anesthesiology, Laboratory of Anesthesia & Critical Care Medicine, Translational Neuroscience Center, West China Hospital of Sichuan University, Chengdu, Sichuan, People's Republic of China
| | | | | | | | | | | |
Collapse
|
13
|
A novel intravenous general anesthetic — emulsified isoflurane: from bench to bedside. Front Med 2012; 6:381-7. [DOI: 10.1007/s11684-012-0229-z] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2012] [Accepted: 09/28/2012] [Indexed: 10/27/2022]
|