Single-base editing in IGF2 improves meat production and intramuscular fat deposition in Liang Guang Small Spotted pigs

Background Chinese indigenous pigs are popular with consumers for their juiciness,flavour and meat quality,but they have lower meat production.Insulin-like growth factor 2(IGF2) is a maternally imprinted growth factor that promotes skeletal muscle growth by regulating cell proliferation and differentiation.A single nucleotide polymorphism(SNP) within intron 3 of porcine IGF2 disrupts a binding site for the repressor,zinc finger BED-type containing 6(ZBED6),leading to up-regulation of IGF2 and causing major effects on muscle growth,heart size,and backfat thickness.This favorable mutation is common in Western commercial pig populations,but absent in most Chinese indigenous pig breeds.To improve meat production of Chinese indigenous pigs,we used cytosine base editor 3(CBE3)to introduce IGF2 intron3-C3071T mutation into porcine embryonic fibroblasts(PEFs) isolated from a male Liang Guang Small Spotted pig(LGSS),and single-cell clones harboring the desired mutation were selected for somatic cell nuclear transfer(SCNT) to generate the founder line of IGF2^(T/T) pigs.Results We found the heterozygous progeny IGF2^(C/T) pigs exhibited enhanced expression of IGF2,increased lean meat by 18%-36%,enlarged loin muscle area by 3%-17%,improved intramuscular fat(IMF) content by 18%-39%,marbling score by 0.75-1,meat color score by 0.53-1.25,and reduced backfat thickness by 5%-16%.The enhanced accumulation of intramuscular fat in IGF2^(C/T) pigs was identified to be regulated by the PI3K-AKT/AMPK pathway,which activated SREBP1 to promote adipogenesis.Conclusions We demonstrated the introduction of IGF2-intron3-C3071T in Chinese LGSS can improve both meat production and quality,and first identified the regulation of IMF deposition by IGF2 through SREBP1 via the PI3KAKT/AMPK signaling pathways.Our study provides a further understanding of the biological functions of IGF2and an example for improving porcine economic traits through precise base editing.

Phase engineering of Ni-Mn binary layered oxide cathodes for sodiumion batteries

Nickel-manganese binary layered oxides with high working potential and low cost are potential candidates for sodium-ion batteries,but their electrochemical properties are highly related to compositional diversity.Diverse composite materials with various phase structures of P3,P2/P3,P2,P2/O3,and P2/P3/O3 were synthesized by manipulating the sodium content and calcination conditions,leading to the construction of a synthetic phase diagram for Na_(x)Ni_(0.25)Mn_(0.75)O_(2)(0.45≤x≤1.1).Then,we compared the electrochemical characteristics and structural evolution during the desodiation/sodiation process of P2,P2/P3,P2/03,and P2/P3/O3-Na_(x)Ni_(0.25)Mn_(0.75)O_(2).Among them,P2/P3-Na0.75Ni0.25Mn0.75O2exhibits the best rate capability of 90.9 mA h g^(-1)at 5 C,with an initial discharge capacity of 142.62 mA h g^(-1)at 0.1 C and a capacity retention rate of 78.25%after 100 cycles at 1 C in the voltage range of 2-4.3 V.The observed superior sodium storage performance of P2/P3 hybrids compared to other composite phases can be attributed to the enhanced Na^(+)transfer dynamic,reduction of the Jahn-teller effect,and improved reaction reversibility induced by the synergistic effect of P2 and P3 phases.The systematic research and exploration of phases in Na_(x)Ni_(0.25)Mn_(0.75)O_(2)provide new sights into high-performance nickel-manganese binary layered oxide for sodium-ion batteries.

Allelopathic Potential and Mechanism of Rosebay Willowherb[Chamaenerion angustifolium(L.)Scop.]Demonstrated on Model Plant Lettuce

Allelopathic plants are important resources for the discovery of bioherbicides.Rosebay willowherb[Chamaenerion angustifolium(L.)Scop.syn.Epilobium angustifolium L.]widely distributes in Western Asia,Europe,and North America,and behaves as a dominant species within the community due to the production of substances that restrict growth of other plants.This study aims at investigating the allelopathic potential of rosebay willowherb by evaluation of the effects of aqueous extracts from different parts on seed germination and seedling growth in lettuce(Lactuca sativa L.),as well as measuring the accumulation of reactive oxygen species and structural analysis of root tips via scanning electron and transmission electron microscopy.It was observed that the aqueous extracts from the leaves of rosebay willowherb had the strongest inhibitory effect on the germination index,germination energy and total germination of lettuce seeds,followed by capsular fruits and flowers,and the inhibition effect of stems was the weakest.All aqueous extracts(100 mg/mL)showed a significant inhibitory effect on radicle elongation of lettuce seedlings.Additionally,after treatment with the aqueous extract of rosebay willowherb leaves,accumulation of reactive oxygen species increased in columella cells,which correlated with disruption of root tip structure.

CTCs Detection and Whole-exome Sequencing Might Be Used to Differentiate Benign and Malignant Pulmonary Nodules

Background and objective Low-density computed tomography(LDCT)improved early lung cancer diagnosis but introduces an excess of false-positive pulmonary nodules data.Hence,accurate diagnosis of early-stage lung cancer remains challenging.The purpose of the study was to assess the feasibility of using circulating tumour cells(CTCs)to differentiate malignant from benign pulmonary nodules.Materials and methods 122 patients with suspected malignant pulmonary nodules detected on chest CT in preparation for surgery were prospectively recruited.Peripheral blood samples were collected before surgery,and CTCs were identified upon isolation by size of epithelial tumour cells and morphological analysis.Laser capture microdissection,MALBAC amplification,and whole-exome sequencing were performed on 8 samples.The diagnostic efficacy of CTCs counting,and the genomic variation profile of benign and malignant CTCs samples were analysed.Results Using 2.5 cells/5 m L as the cut-off value,the area under the receiver operating characteristic curve was of 0.651(95%confidence interval:0.538-0.764),with a sensitivity and specificity of 0.526 and 0.800,respectively,and positive and negative predictive values of 91.1%and 30.3%,respectively.Distinct sequence variations differences in DNA damage repair-related and driver genes were observed in benign and malignant samples.TP53 mutations were identified in CTCs of four malignant cases;in particular,g.7578115T>C,g.7578645C>T,and g.7579472G>C were exclusively detected in all four malignant samples.Conclusion CTCs play an ancillary role in the diagnosis of pulmonary nodules.TP53 mutations in CTCs might be used to identify benign and malignant pulmonary nodules.

学科交叉视域下高锰酸钾法测定水样中化学需氧量实验的设计与实践

新工科背景下的复合型人才培养需要学科的交叉融合。以学科交叉为切入点,对无机及分析化学实验课程实验教学进行了改革和实践。以校内自来水和生活污水作为测试对象,采用高锰酸钾法测定了水样的化学需氧量。通过实验旨在提高学生的实践动手能力、跨学科思维能力、数据收集计算能力以及解决实际问题能力,增强学生环境保护意识,适合为化学、环境工程和资源循环科学与工程等专业学生开课。问卷调查发现,学生和教师对该实验内容都给予了高度评价,教学实践效果良好。

Cu-Zn原电池标准电动势测定实验的计算化学设计

基于量子化学计算软件Gaussian 16,对“电动势的测定”这一经典物理化学实验进行了计算化学设计。用密度泛函方法计算了Cu^(2+)和Zn^(2+)的溶剂化自由能,通过热力学循环计算得到电池反应的标准摩尔吉布斯自由能变,进而求出Cu-Zn原电池的标准电动势。该实验旨在帮助学生加深对标准摩尔吉布斯自由能、电极电势和能斯特方程等物理化学基本概念的理解,发挥学生的主观能动性,培养学生设计实验能力、动手实践能力以及科学思维。

Tunable vacancy defect chemistry on free-standing carbon cathode for lithium-sulfur batteries

The defect chemistry is successfully modulated on free-standing and binder-free carbon cathodes for highly efficient Li-S redox reactions.Such rationally regulated defect engineering realizes the synchronization of ion/electron-conductive and defect-rich networks on the threedimension carbon cathode,leading to its tunable activity for both relieving the shuttle phenomenon and accelerating the sulfur redox reaction kinetics.As expected,the defective carbon cathode harvests a high rate capacity of 1217.8 mAh g^(-1)at 0.2 C and a superior capacity retention of61.7%at 2 C after 500 cycles.Even under the sulfur mass loading of 11.1 mg cm^(-2),the defective cathode still holds a remarkable areal capacity of 8.5 mAh cm^(-2).

Effects of Huangzhou Radish Powder on the Quality of Silver Carp Surimi Products

[Objectives]This study was conducted to improve the quality of frozen silver carp surimi products.[Methods]Huangzhou radish powder and silver carp surimi were used as raw materials to analyze the effects of different amounts(1%,2%,3%,4%,5%)of Huangzhou radish powder on the water-holding capacity,cooking loss rate,whiteness value,TPA,gel strength and sensory quality of surimi products.[Results]When the addition amount of Huangzhou radish powder was 1%,water-holding capacity,hardness,chewiness and the gel strength of the surimi product reached their maximum values,which were 86.86%,3470.36 g,2628.50 g and 707.48 g·mm,respectively.Meanwhile,the cooking loss rate was reduced to a minimum value(13.66%),and the sensory quality reached the best.The whiteness of surimi products showed a decreasing trend with the increase of the addition amount of Huangzhou radish powder.However,the whiteness of the surimi product was not significantly affected when the addition amount of Huangzhou radish powder was 1%.Therefore,when the addition amount of Huangzhou radish powder was 1%,the quality of surimi products could be improved.[Conclusions]This study provides a new idea for the development and utilization of Huangzhou radish.

Action Mechanism of Radix Aucklandiae against Gastric Ulcer Based on Network Pharmacology

[Objectives] To explore the potential targets and action mechanism of radix aucklandiae (RA) in the treatment of gastric ulcer (GU) by network pharmacology. [Methods] Gene targets were obtained through TCMSP, DisGeNet, OMIM, GeneCards databases, which related to GU and the active components of RA. The mutual potential functional targets were selected through Venny to constitute the PPI protein interaction network. The DAVID database was applied for GO and KEGG enrichment analysis of the common targets to construct the "Active component-Target-Pathway" network and analyze the relationship between them. [Results] There are 31 active components, 82 related targets and 16 common targets in the treatment of GU. The active components in Ra may exert anti-ulcer effects through six signaling pathways, including NF-κB, Toll-like receptors, VEGF and HIF-1. In addition, PTGS2, TNF, TLR4, JUN, IL2, SRC, RELA, KDR, NOS2 and PLAU may be the 10 key targets of Ra in the treatment of GU. [Conclusions] Ra controls GU through the synergies of multiple components, targets and pathways. It can provide a theoretical basis for further study on the mechanism of RA in treating GU.

编辑MSTN半胱氨酸节基元促进两广小花猪肌肉生长

肌生长抑制素(myostatin,MSTN)是转化生长因子β(transforming growth factor-β,TGF-β)家族成员之一,是一种肌肉生长抑制因子。解除MSTN的生长抑制功能是提高畜禽肌肉产量的一种有效途径。TGF-β的半胱氨酸节结构基元(cystine knot motif)能够稳定MSTN蛋白结构,对MSTN生物学功能的发挥具有重要调控作用。本研究应用CRISRP/Cas9基因编辑技术在两广小花猪肾细胞(Liang Guang small spotted pig kidney cells,LPKCs)中对MSTN基因外显子3进行编辑,破坏了其半胱氨酸节基元,以解除MSTN对靶基因的抑制功能。将流式分选获得的混合阳性MSTN编辑LPKCs作为供体细胞进行核移植和胚胎移植,获得8头MSTN基因编辑两广小花猪仔猪,其中2头存活至10日龄,经鉴定这2头均为基因编辑杂合子,它们在构成MSNT蛋白半胱氨酸节基元的两个半胱氨残基C106和C108编码序列附近分别发生碱基的缺失与替换,导致移码突变,使C106和C108突变为其他氨基酸。MSTN基因编辑两广小花猪杂合子肩部和臀部肌肉较为发达。H&E切片分析显示,MSTN基因编辑猪肌纤维横截面积显著减少,肌纤维数量显著增多。Western Blot分析结果显示,C106和C108缺失对MSTN蛋白表达无显著性影响,但显著促进其靶基因Myf5、MyoD和Myogenin等成肌相关因子的表达。本研究获得的基因编辑猪模型没有造成MSTN表达完全缺失,可保留MSTN其他生物学功能,在促进两广小花猪肌肉生长的同时还消除了MSTN完全缺失可能对小花猪造成的潜在影响。

利用CRISPR/Cas9系统构建人HPRT1基因定点突变细胞株

Hypoxanthine-guanine phosphoribosyltransferase1(HPRT1)基因突变会导致次黄嘌呤和鸟嘌呤代谢异常,严重的代谢障碍被称为Lesch-Nyhan综合征,表现为智力低下,行为上出现强迫性自我毁伤,并伴随痛风或肾结石等症状。HPRT1基因具有多种突变模式,近年来对其突变谱的研究表明该基因具有一些"突变热点"。本研究选取了导致翻译提前终止的热点突变c.508C>T突变和c.151C>T突变,在HEK293T和HeLa细胞中,以单链寡核苷酸(single-stranded oligo-deoxyribonucleotides,ssODN)作为同源重组模板,利用CRISPR/Cas9技术构建了这两种突变的单克隆细胞株,发生定点突变的效率分别为16.3%和10%。进一步通过Westernblot检测点突变的单克隆细胞的HPRT1蛋白表达水平,通过6-TG毒性实验检测点突变的单克隆细胞的次黄嘌呤/鸟嘌呤磷酸核糖转移酶活性,结果表明纯合突变的单细胞克隆不能正常表达HPRT1蛋白,其次黄嘌呤/鸟嘌呤磷酸核糖转移酶活性丧失;杂合突变的单细胞克隆的HPRT1蛋白表达量降低,仍具有部分次黄嘌呤/鸟嘌呤磷酸核糖转移酶活性。HPRT1基因定点突变细胞模型的建立可为今后建立其他HPRT1基因突变的细胞系或动物模型提供借鉴,为研究Lesch-Nyhan致病机制提供基础。

城市家长对学前融合教育的接纳度

家长对学前融合教育的接纳度是顺利开展学前融合教育的前提和保障。以河南省15所城市幼儿园家长为例,通过编制科学有效的问卷,从认知、情感和行为三个维度对900名家长进行调查,结果发现家长对学前融合教育在认知、情感和行为方面的接纳度均比较高,但是对相关概念和法律意识的接纳度较低。对学前融合教育接纳度的人口统计学分析显示,家长的接纳度在性别、年龄上存在显著差异,在学历上无显著差异。家长对学前融合教育接纳度不高的主要原因在于社会宣传不够,广大民众不了解;幼儿园缺乏开展学前融合教育的资源,相关师资力量匮乏等。为促进家长对学前融合教育的接纳度,应扩大社会舆论宣传,提高民众对特殊儿童的关注;加大职前融合教育师资的培养,提高教师的融合教育专业能力;为幼儿园提供充分的相关支持;研究者应加快有关学前融合教育的理论研究。

Changes in compressed neurons from dogs with acute and severe cauda equina constrictions following intrathecal injection of brain-derived neurotrophic factor-conjugated polymer nanoparticles

This study established a dog model of acute multiple cauda equina constriction by experimental constriction injury (48 hours) of the lumbosacral central processes in dorsal root ganglia neurons. The repair effect of intrathecal injection of brain-derived neurotrophic factor with 15 mg encapsulated biodegradable poly(lactide-co-glycolide) nanoparticles on this injury was then analyzed. Dorsal root ganglion cells (L7) of all experimental dogs were analyzed using hematoxylin-eosin staining and immunohistochemistry at 1, 2 and 4 weeks following model induction. Intrathecal injection of brain-derived neurotrophic factor can relieve degeneration and inflammation, and elevate the expression of brain-derived neurotrophic factor in sensory neurons of compressed dorsal root ganglion. Simultaneously, intrathecal injection of brain-derived neurotrophic factor obviously improved neurological function in the dog model of acute multiple cauda equina constriction. Results verified that sustained intraspinal delivery of brain-derived neurotrophic factor encapsulated in biodegradable nanoparticles promoted the repair of histomorphology and function of neurons within the dorsal root ganglia in dogs with acute and severe cauda equina syndrome.

Two-moment Bulk Stratiform Cloud Microphysics in the Grid-point Atmospheric Model of IAP LASG (GAMIL)

A two-moment bulk stratiform microphysics scheme, including recently developed physically-based droplet activation/ice nucleation parameterizations has been implemented into the Grid-point Atmospheric Model of IAP LASG (GAMIL) as an effort to enhance the model's capability to simulate aerosol indirect effects. Unlike the previous one-moment cloud microphysics scheme, the new scheme produces a reasonable representation of cloud particle size and number concentration. This scheme captures the observed spatial variations in cloud droplet number concentrations. Simulated ice crystal number concentrations in cirrus clouds qualitatively agree with in situ observations. The longwave and shortwave cloud forcings are in better agreement with observations. Sensitivity tests show that the column cloud droplet number concentrations calculated from two different droplet activation parameterizations are similar. However, ice crystal number concentration in mixed-phased clouds is sensitive to different heterogeneous ice nucleation formulations. The simulation with high ice crystal number concentration in mixed-phase clouds has less liquid water path and weaker cloud forcing. Furthermore, ice crystal number concentration in cirrus clouds is sensitive to different ice nucleation parameterizations. Sensitivity tests also suggest that the impact of pre-existing ice crystals on homogeneous freezing in old clouds should be taken into account.

Preparation and evaluation of sustained-release diltiazem hydrochloride pellets

In this study,diltiazem hydrochloride(DTZ)pellets were prepared successfully by extrusionespheronization method.Then methacrylic acid and ethylcellulose coating formulations were employed to make the DTZ pellets sustained release.The pellets with different coatings were investigated by in vitro dissolution tests.At last,the pellets with the best coating copolymer were subjected to pharmacokinetic studies in beagle dogs.The dissolution profiles of pellets coated with Eudragit
NE30D were similar to Herbesser
,one of the marketed sustained release capsules.In the bioavailability study,the principal pharmacokinetic parameters of self-made pellets and the marketed ones were comparable;the relative bioavailability of DTZ sustained release capsules compared with Herbesser
was 98.5
36.4%.All the data indicated self-made sustained pellets could prolong the release of DTZ,decrease the fluctuation of drug level in vivo,and increase the compliance of patients.

Pharmacokinetics of oxiracetam and its degraded substance (HOPAA) after oral and intravenous administration in rats

The pharmacokinetics of oxiracetam and its degraded substance(4-hydroxy-2-oxo-1-pyrrolidine acetic acid,HOPAA)after oral and intravenous administration in rats were studied using an established UPLC-MS/MS method.Three groups of rats after an overnight fasted received 10 g/kg(n=6)oxiracetam suspensions orally,and 2 g/kg(n=6)normal or degraded oxiracetam injections intravenously via a caudal tail vein,respectively.Before the pharmacokinetic experiment,a simple safety evaluation testwas conducted on the degraded oxiracetam injections containing 16.16% HOPAA in mice.There was no mortality by a single intravenous dose of 2 g/kg of degraded oxiracetam injections within twoweeks,demonstrating that HOPAA was non-toxic in mice.Following intravenous administration of the normal injections,the plasma concentration-time curves of oxiracetam and HOPAA both showed a rapid elimination phase.The values of t_(1/2)were 3.1±1.5 h for oxiracetamand 0.8±0.2 h for HOPAA,andthemean residencetimes(MRT)were 1.2±0.1h and 0.8±0.1h,respectively.Oxiracetam and HOPAA after intravenous administration of the degraded oxiracetam injections presented elimination patterns similar to those observed in the normal injections.Oral pharmacokinetic results showed that the Tmax was less than 1.5 h for the two analytes,and both had a longer t_(1/2) and MRT than those of intravenous administration.Contents of HOPAA in three groupswere calculated based on AUC_(0-t) values of the two analytes.The quantitative change of HOPAA in vivo was also evaluated by comparing the plasma concentrations of HOPAA and oxiracetamat the same time for every group.Additionally,the values of absolute bioavailability of oxiracetam were about 8.0%and 7.4%calculated by the normal or degraded oxiracetam injections,whichwere far less than the value of 75%reported in literature,indicating the necessity of further study.

Early ABA-stimulated maintenance of Cl^(−) homeostasis by mepiquat chloride priming confers salt tolerance in cotton seeds

Mepiquat chloride(MC)priming alleviates the effects of salt stress during seed germination in cotton(Gossypium hirsutum L.),but the mechanisms underlying its effects are unknown.We found that MC priming increases salt tolerance,as evidenced by marked increases in seed vigor and germination rates,and alleviated salt toxicity by reducing Cl^(−)accumulation in germinating seeds.Consistently,electrophysiological experiments revealed that the seeds with MC priming displayed superior Cl^(−)exclusion ability in the root apex.These beneficial effects of MC priming were abolished by the abscisic acid(ABA)-synthesis blocker fluridone under salt stress.MC priming induced an early response to acclimatization and stress,as indicated by rapidly increasing ABA content during initial exposure to salt stress.Transcriptome analyses revealed that MC priming induced an array of differentially expressed genes(DEGs)in germinating seeds.The most noticeable changes in germinating seeds were MC priming-induced increases in the expression of DEGs encoding components of ABA biosynthesis,ABA catabolism,and ABA signaling pathways under salt stress.MC priming also increased the expression of some DEGs encoding Cl^(−)ion transporters(e.g.CCC,SLAC1/SLAH1/SLAH3,CLC,and ALMT9)in germinating seeds.These results indicate that MC priming-induced ABA contributes to Cl^(−)homeostasis in tissues and acts as a positive regulator of salt tolerance via regulation of Cl^(−)transporters(particularly CCC and SLAC1/SLAH1/SLAH3).Taken together,these findings shed light on the molecular mechanism underlying MC-mediated tolerance to salt stress during seed germination.

Gradient high performance liquid chromatography method for simultaneous determination of ilaprazole and its related impurities in commercial tablets

A methodology(HPLC)proposed in this paper for simultaneously quantitative determination of ilaprazole and its related impurities in commercial tablets was developed and validated.The chromatographic separation was carried out by gradient elution using an Agilent C8 column(4.6 mm×250 mm,5 mm)which was maintained at 25℃.The mobile phase composed of solvent A(methanol)and solvent B(solution consisting 0.02 mmol/l monopotassium phosphate and 0.025 mmol/l sodium hydroxide)was at a flow rate of 1.0 ml/min.The samples were detected and quantified at 237 nm using an ultraviolet absorbance detector.Calibration curves of all analytes from 0.5 to 3.5 mg/ml were good linearity(r≥0.9990)and recovery was greater than 99.5% for each analyte.The lower limit of detection(LLOD)and quantification(LOQ)of this analytical method were 10 ng/ml and 25 ng/ml for all impurities,respectively.The stress studies indicated that the degradation products could not interfere with the detection of ilaprazole and its related impurities and the assay can thus be considered stability-indicating.The method precisions were in the range of 0.41-1.21 while the instrument precisions were in the range of 0.38-0.95 in terms of peak area RSD% for all impurities,respectively.This method is considered stabilityindicating and is applicable for accurate and simultaneous measuring of the ilaprazole and its related impurities in commercial enteric-coated tablets.

Development and validation of a UPLC–MS/MS assay for the determination of gemcitabine and its L-carnitine ester derivative in rat plasma and its application in oral pharmacokinetics

A simple and rapid UPLC–MS/MS method to simultaneously determine gemcitabine and its L-carnitine ester derivative(2’-deoxy-2’, 2’-difluoro-N-((4-amino-4-oxobutanoyl) oxy)-4-(trimethyl amm-onio) butanoate-cytidine, JDR) in rat plasma was developed and validated.The conventional plasma sample preparation method of nucleoside analogues is solidphase extraction(SPE) which is time-consuming and cost-expensive. In this study, gradient elution with small particles size solid phase was applied to effectively separate gemcitabine and JDR, and protein precipitation pretreatment was adopted to remove plasma protein and extract the analytes with high recovery(>81%). Method validation was performed as per the FDA guidelines, and the standard curves were found to be linear in the range of 5–4000 ng/ml for JDR and 4–4000 ng/ml for gemcitabine, respectively. The lower limit of quantitation(LLOQ)of gemcitabine and JDR was 4 and 5 ng/ml, respectively. The intra-day and inter-day precision and accuracy results were within the acceptable limits. Finally, the developed method was successfully applied to investigate the pharmacokinetic studies of JDR and gemcitabine after oral administration to rats.

N-methyl-D-aspartate receptor expression in the spinal dorsal horn of a rat model of formalin-induced inflammatory pain following intrathecal injection of butorphanol

Clinical and animal experiments have proved that intrathecal injection of butorphanol has an analgesic effect. However, whether the analgesic effect is associated with activation of the N-methyl-D-aspartate (NMDA) receptor remains unclear. This study presumed that intrathecal injection of butorphanol has an analgesic effect on formalin-induced inflammatory pain in rats, and its analgesic effect is associated with inhibition of NMDA receptors. Concurrently, ketamine was injected into the intrathecal space, which is a non-competitive NMDA receptor antagonist, to determine the analgesic mechanism of butorphanol. The total reflection time in phase 1 and phase 2 of rat hind paws carding action was reduced when the butorphanol dose was increased to 25 μg, or a low dose of butorphanol was combined with ketamine. Intrathecal injection of a high dose of butorphanol alone or a low dose of butorphanol combined with ketamine can remarkably reduce NMDA receptor expression in the L5 spinal dorsal horn of formalin-induced pain rats. The results suggest that intrathecal injection of butorphanol has analgesic effects on formalin-induced inflammatory pain, and remarkably reduces NMDA receptor expression in the rat spinal dorsal horn. Ketamine strengthens this analgesic effect. The analgesic mechanism of intrathecal injection of butorphanol is associated with inhibition of NMDA receptor activation.