[Complete chloroplast genome sequencing and phylogeny of wild Atractylodes lancea from Yuexi, Anhui province].

This study investigated the choroplast genome sequence of wild Atractylodes lancea from Yuexi in Anhui province by high-throughput sequencing, followed by characterization of the genome structure, which laid a foundation for the species identification, analysis of genetic diversity, and resource conservation of A. lancea. To be specific, the total genomic DNA was extracted from the leaves of A. lancea with the improved CTAB method. The chloroplast genome of A. lancea was sequenced by the high-throughput sequencing technology, followed by assembling by metaSPAdes and annotation by CPGAVAS2. Bioiformatics methods were employed for the analysis of simple sequence repeats(SSRs), inverted repeat(IR) border, codon bias, and phylogeny. The results showed that the whole chloroplast genome of A. lancea was 153 178 bp, with an 84 226 bp large single copy(LSC) and a 18 658 bp small single copy(SSC) separated by a pair of IRs(25 147 bp). The genome had the GC content of 37.7% and 124 genes: 87 protein-coding genes, 8 rRNA genes, and 29 tRNA genes. It had 26 287 codons and encoded 20 amino acids. Phylogenetic analysis showed that Atractylodes species clustered into one clade and that A. lancea had close genetic relationship with A. koreana. This study established a method for sequencing the chloroplast genome of A. lancea and enriched the genetic resources of Compositae. The findings are expected to lay a foundation for species identification, analysis of genetic diversity, and resource conservation of A. lancea.

Electroacupuncture relieves hyperalgesia by regulating neuronal-glial interaction and glutamate transporters of spinal dorsal horns in rats with acute incisional neck pain.

Objective: Glial cells are involved in the analgesic effect of electroacupuncture (EA) in rats with chronic neurological pain. The objective of this study was to observe the role of neuronal-glial interaction and glutamate (Glu) transporters in EA-induced acute neck pain relief in rats. Materials and methods: Male rats were placed into the following five groups: control, model, EA Futu (LI18), EA Hegu (LI4)-Neiguan (PC6), and EA Zusanli (ST36)-Yanglingquan (GB34). The incisional neck pain model was established by making a longitudinal incision along the midline of the neck. The thermal pain threshold (TPT) was measured using a radiation heat detector. The immunoactivities of glial fibrillary acidic protein (GFAP), ionized calcium-binding adapter molecule 1 (Iba-1), neurokinin-1 receptor (NK-1R), Glu aspartate transporter (GLAST), and Glu transporter-1 (GLT-1) in the dorsal horns (DHs) of the cervico-spinal cord (C2-C5) were detected using immunofluorescence histochemistry. The expression levels of GFAP, Iba-1, GLAST, and GLT-1 mRNAs were determined using quantitative real-time polymerase chain reaction (PCR). Results: The TPT and levels of mRNAs expression and immunoactivity of GLT-1 and GLAST were significantly decreased, and those of Iba-1 and GFAP were significantly increased in the model group than those of the control group (P < 0.05). The activated microgliacytes were gathered around the NK-1R positive neurons, and co-expression of NK-1R and astrocytes was observed in the model group. EA LI18 significantly increased the TPT and expression of GLAST and GLT-1 mRNAs (P < 0.05) and notably decreased the number of Iba-1 positive cells and Iba-l mRNA expression (P < 0.05), whereas GLAST and GLT-1 antagonists inhibited the analgesic effect of EA LI18. However, these effects, except for the downregulation of Iba-1 mRNA, were not observed in the EA ST36-GB34 group. Fewer NK-1R-positive neurons were visible in the spinal DHs in the EA LI18 group, and the co-expression of NK-1R and astrocytes was also lower than that in the three EA groups. Conclusion: Electroacupuncture of LI18 had an analgesic effect in rats with neck incisions, which may be related to its functions in suppressing the neuronal-glial cell interaction through NK-1R and upregulating the expression of GLAST and GLT-1 in the spinal DHs.

[κ-opioid receptor is involved in electroacupuncture analgesia via inhibition of spinal microglial Toll-like receptor 4 in neuropathic pain rats].

OBJECTIVE: To observe the effect of electroacupuncture (EA) on the expression of lumbar spinal κ-opioid receptor (KOR) and Toll-like receptor 4(TLR4) in microglia in neuropathic pain rats, so as to explore the role of cross-talk between KOR and TLK4 in EA-induced alleviation of chronic neuropathic pain. METHODS: Wistar male rats were randomized into control, model, EA and EA plus KOR inhibitor (EA+inhibitor) groups (n=18 in each group). The neuropathic pain model was established in rats by ligature of the right sciatic nerve. EA was applied at bilateral "Zusanli"(ST36) and "Yanglingquan"(GB34) for 30 min, once daily for 5 days. JDTic dihydrochloride (a KOR inhibitor) was administrated by intraperitoneal injection before EA intervention. The difference value of paw withdrawal thermal latency (PWLD) of the bilateral hind-limbs was used as the thermal pain reaction level. At the end of experiments, the rat's lumbar spinal cord (L2-L4) was taken for detecting the expression of CD68 mRNA (a marker of the activated microglia) and Iba-1 (a marker for the activated and resting microglia) immunoactivity, and dynorphin content, and KOR mRNA and TLR4 protein (in immunomagnetic microbead method separated microglia) by using fluorescence quantitative PCR, immunofluorescence, radioimmunoassay and Western blot, separately. RESULTS: Compared with the control group, a strong thermal hyperalgesia was induced, the expression levels of Iba-1 and CD68 mRNA in the spinal cord, TLR4 protein of the spinal microglia were significantly increased(P<0.01) in the model group. The microglia were characterized by somatic hypertrophy and thickened branches in the model group. After EA intervention, the PWLD, the expression of Iba-1, CD68 mRNA and TLR4 protein of the microglia were significantly decreased(P<0.05), while the content of spinal dynorphin and the expression of KOR mRNA of the microglia increased in the EA group relative to the model group(P<0.05). The hypertrophic microglia shrinked slightly in the EA group. After injection of KOR inhibitor, the PWLD and expression levels of Iba-1, CD68 mRNA and TLR4 protein were significantly increased(P<0.05), and the expression of KOR mRNA was significantly decreased(P<0.05) in the EA+inhibitor group in comparison with the EA group. CONCLUSION: The analgesia effect of EA may partly mediated by spinal microglial KOR and the activation of KOR of microglia may be a target for inhibition of microglial TLR4-induced pro-inflammatory signaling.

[Spinal cord Toll like receptor 4 and its co-stimulatory molecule heat shock protein 90 may parti-cipate in electroacupuncture analgesia in rats with chronic neuropathic pain].

OBJECTIVE: To observe the effect of electroacupuncture (EA) on the expression of Toll like receptor 4(TLR4)and heat shock protein 90(HSP90) in the spinal cord of rats with chronic constriction injury (CCI) of sciatic nerve, so as to explore the mechanism of spinal cord TLR4 and HSP90 in alleviating chronic neuropathic pain by EA. METHODS: Male Wistar rats were randomized into control, model, EA, HSP90 inhibitor (inhibitor) and EA+ inhibitor groups (n=10 in each group). The neuropathic pain model was established by ligature of the right sciatic nerve to induce CCI. EA (1 mA，2 Hz/15 Hz)was applied at bilateral "Zusanli"(ST36) and "Yanglingquan"(GB34) for 30 min, once daily for 5 days. Rats of the inhibitor and EA+inhibitor groups were given a subcutaneous injection of HSP90 inhibitor geldanamycin (50 µg/kg) at the neck before daily EA. The paw withdrawal latency (PWL) of the bilateral hind-limbs was detected by using an algesia-detector. The contents of interleukin 1ß (IL-1ß) and tumor necrosis factor α (TNF-α) in the lumbar spinal cord (L2-L4) tissue were detected by enzyme-linked immunosorbent assay. The relative expression levels of HSP90 and TLR4 proteins in the lumbar spinal cord (L2-L4) were detected using Western blot and immunofluorescence double labeling, respectively. RESULTS: Following CCI, a strong thermal hyperalgesia, an apparent up-regulation of expression of HSP90 and TLR4 proteins and TLR4 in microglia, and increasing levels of IL-1ß and TNF-α in the spinal cord were induced in the model group relevant to the control group (P<0.01，P<0.05). Five sessions of EA intervention or inhibitor injection significantly attenuated hyperalgesia, reversed the increase of IL-1ß and TNF-α, and down-regulated the expression of TLR4 in microglia (P<0.05). Compared with the model group, the expression of HSP90 was further increased (P<0.05), and those of TLR4 in microglia and neurons were significantly decreased and increased, respectively in the EA group (P<0.05). Compared with the EA group, the levels of PWLD,TLR4 and HSP90 expression, and the proportions of neuronal nuclei antigen（NeuN） and TLR4, and ionized calcium binding adapter molecule （Iba1） and TLR4 co-expressed cells were significantly decreased in the inhibitor group and EA+inhibitor group (P<0.05). The proportion of NeuN and TLR4 co-expression cells in the EA+inhibitor group was significantly higher than that of the inhibitor group (P<0.05). CONCLUSION: EA stimulation of ST36 and GB34 can alleviate thermal hyperalgesia in CCI rats, which is closely associated with its effect in regulating the expression of TLR4 in the spinal cord neurons and microglia. HSP90 in the spinal cord may be a co-stimulatory molecule for EA induced relief of neuropathic pain by regulating TLR4.

Discovery of hCES2A inhibitors from Glycyrrhiza inflata via combination of docking-based virtual screening and fluorescence-based inhibition assays.

Human carboxylesterase 2 (hCES2A) is a key target to ameliorate the intestinal toxicity triggered by irinotecan that causes severe diarrhea in 50%-80% of patients receiving this anticancer agent. Herbal medicines are frequently used for the prevention and treatment of the intestinal toxicity of irinotecan, but it is very hard to find strong hCES2A inhibitors from herbal medicines in an efficient way. Herein, an integrated strategy via combination of chemical profiling, docking-based virtual screening and fluorescence-based high-throughput inhibitor screening assays was utilized. Following the screening of a total of 73 herbal products, licorice (the dried root of Glycyrrhiza species) was found with the most potent hCES2A inhibition activity. Further investigation revealed that the chalcones and several flavonols in licorice displayed strong hCES2A inhibition activities, while isoliquiritigenin, echinatin, naringenin, gancaonin I and glycycoumarin exhibited moderate inhibition of hCES2A. Inhibition kinetic analysis demonstrated that licochalcone A, licochalcone C, licochalcone D and isolicoflavonol potently inhibited hCES2A-mediated fluorescein diacetate hydrolysis in a reversible and mixed inhibition manner, with Ki values less than 1.0 µM. Further investigations demonstrated that licochalcone C, the most potent hCES2A inhibitor identified from licorice, dose-dependently inhibited intracellular hCES2A in living HepG2 cells. In summary, this study proposed an integrated strategy to find hCES2A inhibitors from herbal medicines, and our findings suggested that the chalcones and isolicoflavonol in licorice were the key ingredients responsible for hCES2A inhibition, which would be very helpful to develop new herbal remedies or drugs for ameliorating hCES2A-associated drug toxicity.

GABAergic Inhibition of Spinal Cord Dorsal Horns Contributes to Analgesic Effect of Electroacupuncture in Incisional Neck Pain Rats.

BACKGROUND: Acupuncture has shown to be effective in relieving post-surgical pain. Nonetheless, its underlying mechanisms remain largely unknown. In the present study, we investigated the effect of electroacupuncture (EA) on the expression of GABA, GABA-A receptor (R) and GABA-BR in the spinal cord dorsal horns (DHs), and the involved neural cells in rats with incisional neck pain. MATERIALS AND METHODS: Male SD rats were randomly divided into control, model, Futu (LI18), Hegu-Neiguan (LI4-PC6), and Zusanli-Yanglingquan (ST36-GB34) groups. The incisional neck pain model was established by making a longitudinal incision and repeated mechanical separation along the thyroid gland region. EA (2Hz/100Hz, 1mA) was applied to LI18, LI4-PC6, ST36-GB34 separately for 30min, once at 4, 24 and 48h after incision. The local thermal pain threshold (TPT) of the focus was measured and the expression of GABA, and GABAR proteins and mRNAs detected by immunofluorescence stain and quantitative RT-PCR, respectively. RESULTS: The analgesic effect of LI18 and LI4-PC6 was superior to that of ST36-GB34 in incisional neck pain rats. Moreover, the EA stimulation of LI18 or LI4-PC6 increased the expression of GABA and GABA-Aα2 and GABA-Aß3, GABA-B1, and GABA-B2 mRNAs in spinal DHs 4h after surgery, while GABA-A and GABA-B antagonists inhibited the analgesic effect of LI18. Immunofluorescence double staining showed that GABA was expressed on astrocytes and neurons, and GABA-B expressed only on neurons. CONCLUSION: EA of both LI18 and LI4-PC6 has a good analgesic effect in incisional neck pain rats, which is closely related to their effects in upregulating the expression of GABA and its receptors in spinal DHs. The effects of LI18 and LI4-PC6 EA are obviously better that those of ST36-GB34 EA, and GABA is expressed on neurons and astrocytes.

[Electroacupuncture alleviated incisional neck pain possibly by suppressing TNF-α expression and increasing IL-4/IL-4 receptor signaling in cervical dorsal part of spinal cord in incisio-nal neck pain rats].

OBJECTIVE: To observe the effect of electroacupuncture (EA) on incisional pain and expression of tumor necrosis factor-α (TNF-α), interleukin-10 (IL-10) and interleukin-4 (IL-4) of cervical dorsal part of spinal cord in rats with incisional neck pain, so as to explore its analgesic mechanisms. METHODS: Eighty-four male SD rats were randomly divided into normal control, model, EA-Futu(LI18) and EA-Zusanli(ST36)-Yanglingquan(GB34, EA-ST36-GB34) groups (n=21 in each group). The incisional neck pain model was established by making a longitudinal incision along the bilateral cervical thyroid regions and repeated mechanical separation stimulation. For rats of the EA groups, EA (2 Hz/100 Hz, 1 mA) was applied to bilateral LI18 or ST36-GB34 for 30 min/ time during the surgery, and 20 and 44 h after surgery, respectively. The thermal pain threshold (TPT) of the incisional region was detected. The immunoactivity of TNF-α and IL-10 of the dorsal portion of the cervical spinal cord (C2-C5) was detected by immunofluorescence, and the expression of TNF-α, IL-10, IL-4 and IL-4 receptor (IL-4R) mRNAs was determined by quantitative real-time PCR. RESULTS: Compared with the normal group, the TPT of the incisional area was significantly decreased at 4, 24 and 48 h after neck-incision (P<0.05), the levels of TNF-α mRNA, IL-10 mRNA and TNF-α IL-10 immunoactivity at 24 h were remarkably increased (P<0.05), and the expression of IL-4R mRNA was considerably decreased at 24 h in the model group (P<0.05). Following EA intervention, the TPT, and expression levels of IL-4 mRNA and IL-4R mRNA were significantly increased at 24 h after surgery in the EA-LI18 group relevant to the model group (P<0.05), while the expression level of TNF-α(coexpressed with microgliacytes) in the EA-LI18 group, and TNF-α mRNA expression at 24 h in both EA-LI18 and EA-ST36-GB34 groups, as well as the expression of IL-10 and IL-10 mRNA at 24 h in both EA-LI18 and EA-ST36-GB34 groups were significantly decreased (P<0.05). The effect of EA LI18 was significantly superior to that of EA ST36-GB34 in up-regulating TPT and expression of IL-4 mRNA and IL-4R mRNA at 24 h (P<0.05). CONCLUSION: EA of LI18 has an analgesic effect in incisional neck pain rats, which may be related to its effect in down-regulating the expression of TNF-α, IL-10 and promoting IL-4 /IL-4R signaling in dorsal portions of the cervical spinal cord. The analgesic effect of EA LI18 is better than that of EA ST36-GB34.

Contribution of GABAergic modulation in DRGs to electroacupuncture analgesia in incisional neck pain rats.

PURPOSE: Acupuncture therapy is effective for relieving postoperative pain. Our previous study showed that electroacupuncture (EA) at Futu (LI18) and Hegu (LI4)-Neiguan (PC6) could alleviate incisional neck pain, which was related with its effect in upregulating γ-aminobutyric acid (GABA) expression in cervical (C3-6) dorsal root ganglions (DRGs); but whether its receptor subsets GABAAα2R and GABABR1 in C3-6 DRGs are involved in EA analgesia or not, it remains unknown. MATERIALS AND METHODS: Seventy-five male Sprague Dawley rats were randomized to normal control, model, LI18, LI4-PC6, and Zusanli (ST36)-Yanglingquan (GB34) groups. The incisional neck pain model was established by making a longitudinal incision along the midline of the rats' neck, followed by repeated mechanical stimulation. EA was applied to bilateral LI18, LI4-PC6, or ST36-GB34 for 30 minutes at 4, 24, and 48 hours after operation. The thermal pain threshold of the neck was detected by a tail-flick unit, and the C3-6 DRGs were removed for assaying the immunoactivity of substance P (SP), GABAAα2R, glial fibrillary acidic protein (GFAP; a marker of satellite glial cells [SGCs]), and GABABR1 and the expression of GABAAα2R and GABABR1 mRNA and proteins using immunofluorescence, real-time PCR, and Western blotting, respectively. RESULTS: The cervical thermal pain threshold was significantly lower in the model group than the normal group (P<0.001), indicating hyperalgesia after neck incision, and was considerably increased in both EA-LI18 and LI4-PC6 groups (P<0.001), but not in ST36-GB34 group compared with model group (P>0.05). Immunofluorescence staining showed that GABAAα2 R expressed on SP+ neurons, and GABABR1 on SGCs. EA of LI18 and LI4-PC6 markedly suppressed the modeling-induced upregulation of the immunoactivity of SP (P<0.001 and P<0.01, respectively) and GFAP (P<0.01 and P<0.001, respectively) and significantly reversed neck incision-induced downregulation of the expression of GABAAα2R and GABABR1 mRNAs and proteins (P<0.05). CONCLUSION: EA of LI18 and LI4-PC6 has an analgesic effect in incisional neck pain rats, which is related to its effects in upregulating GABAergic inhibitory modulation on nociceptive peptidergic neurons and SGCs in cervical DRGs.

[High Mobility Group Box 1/ CD 24 Receptor/ß-EP Signaling in "Zusanli" (ST 36) Region Contributes to Electroacupuncture Analgesia in Rats with Neuropathic Pain].

OBJECTIVE: To observe the effect of electroacupuncture (EA) on the expression of high mobility group box 1 (HMGB 1) and its receptor CD 24 proteins and ß-endorphin (ß-EP) content in "Zusanli" (ST 36) region in rats with chronic constriction injury (CCI), so as to explore its mechanisms underlying pain relief. METHODS: Thirty male Wistar rats were rando-mized into control, CCI model and EA groups (n＝ 10 rats in each). The neuropathic pain model was established by ligature of the left sciatic nerve to induce CCI in the model and EA groups, and sham operation was performed in rats of the control group. Paw with drawal latency (PWL, thermal pain threshold) of the bilateral hind-limbs was detected by using an algesia-detector. Eight days after CCI operation, EA was applied to bilateral "Zusanli" (ST 36) and "Yanglingquan" (GB 34) for 30 min, once daily for 5 days. The acetylated-HMGB 1 expression was determined by immunoprecipitation, and the expression of HMGB 1 and toll like receptor 4 (TLR 4) proteins and CD 24 mRNA were detected using Western blot and fluorescent quantitative real time-PCR, respectively, and the content of ß-EP in the acupoint region was assayed by enzyme linked immunosorbent assay (ELISA). Anti-CD 24 neutralizing antibody (200 µL, 100 µg/mL) was injected into ST 36 region once daily for 3 days for verifying the involvement of HMGB 1/CD 24 signaling in EA analgesia. RESULTS: Compared with the control group, the bilateral PWL difference values in the other two groups were significantly increased (P<0.05), meaning an occurrence of hyperalgesia after CCI. In comparison with the CCI model group, the hyperalgesia in the EA group was obviously decreased (P<0.05). After CCI, the expression levels of HMGB 1 and TLR 4 proteins were considerably increased compared with those in the control group (P<0.05). After 5-times' EA, the acetylated-HMGB 1, the expression of CD 24 mRNA, and the content of ß-EP were notably up-regulated (P<0.05), and there were no obvious changes in the expression levels of HMGB 1 and TLR 4 proteins (P>0.05). After local injection of anti-CD 24 antibody, EA-induced increases of ß-EP content and reduction of thermal pain threshold were significantly suppressed (P<0.05). CONCLUSION: EA of ST 36 and GB 34 can alleviate neuropathic pain in CCI rats, which is associated with its effects in up-regulating ß-EP content, and HMGB 1 protein and CD 24 mRNA expression levels in ST 36 region. The activated HMGB 1/CD 24/ß-EP signaling contributes to EA-ST 36 induced analgesia.

Repeated electroacupuncture treatment attenuated hyperalgesia through suppression of spinal glial activation in chronic neuropathic pain rats.

BACKGROUND: Cumulated evidence reveals that glial cells in the spinal cord play an important role in the development of chronic neuropathic pain and are also complicated in the analgesic effect of EA intervention. But the roles of microgliacytes and astrocytes of spinal cord in the process of EA analgesia remain unknown. METHODS: A total of 120 male Wistar rats were used in the present study. The neuropathic pain model was established by chronic constrictive injury (CCI) of the sciatic nerve. The rats were randomly divided into sham group, CCI group, and sham CCI + EA group, and CCI + EA group. EA was applied to bilateral Zusanli (ST36)-Yanlingquan (GB34). The mechanical (both time and force responses) and thermal pain thresholds (PTs) of the bilateral hind-paws were measured. The number of microgliacytes and activity of astrocytes in the dorsal horns (DHs) of lumbar spinal cord (L4-5) were examined by immunofluorescence staining, and the expression of glial fibrillary acidic protein (GFAP) protein was detected by western blot. RESULTS: Following CCI, both mechanical and thermal PTs of the ipsilateral hind-paw were significantly decreased beginning from the 3rd day after surgery (P < 0.05), and the mechanical PT of the contralateral hind-paw was considerably decreased from the 6th day on after surgery (P < 0.05). CCI also significantly upregulated the number of Iba-1 labeled microgliacytes and the fluorescence intensity of glial fibrillary acidic protein (GFAP) -labeled astrocyte in the superficial laminae of DHs on bilateral sides (P < 0.05). After repeated EA, the mechanical and thermal PTs at bilateral hind-paws were significantly relieved (P < 0.05). The increased of number of microgliacytes was markedly suppressed by 2 days' EA intervention, and the average fluorescence intensity was suppressed by 2 weeks' EA. The expression of GFAP protein were down-regulated by 1 and 2 weeks' EA treatment, respectively (P < 0.05). CONCLUSIONS: Repeated EA can relieve neuropathic pain and mirror-image pain in chronic neuropathic pain rats, which is probably associated with its effect in downregulating glial cell activation of the lumbar spinal cord, the microgliacyte first and astrocyte later.

[Effect of Electroacupuncture Intervention on Expression of Synaptic Plasticity-related Molecules in Amygdala in Chronic Pain-negative Affection Rats].

OBJECTIVE: To observe the effect of electroacupuncture (EA) on expression of synaptic plasticity-related glutamate N-methyl-D-aspartate (NMDA) receptor subunit NR 1, gamma-aminobutyric acid (GABA) receptor subunits (Aß 2, B 1), etc. in the amygdala in chronic neuropathic pain negative affection (CNPPNA) rats, so as to reveal its mechanism underlying pain relief. METHODS: Male Wistar rats were randomized into normal control, CNPPNA model, EA, and anesthesia+EA (AEA)groups (n=14 in each group, 8 for quantitative RT-PCR and 6 for immunofluorescence staining). The CNPPNA model was established by ligation of the left sciatic nerve and repeated electrical stimulation of the hindpaw plantar skin in the pain-paired compartment. EA was applied to bilateral "Zusanli"(ST 36)and "Yanglingquan"(GB 34)for 30 min, once daily for 7 days.Thermal pain threshold (paw withdrawal latency, PWL)of the bilateral paws was measured by using a Tail-Flick Unit. The conditioned place aversion (CPA) was determined by using a CPA-paired compartment. The expression levels of GABAAß 2, GABAB 1, NMDA receptor subunit NR 1, postsynaptic density-95 protein(PSD-95), Piccolo genes in the right amygdala area were determined using quantitative RT-PCR, and the immunoactivity of metabotropic glutamate receptor subunit 1 (mGluR 1) and GABAB 2 in the basolateral amygdala (BLA) nucleus was detected using immunofluorescence staining. RESULTS: After modeling, PWL difference (PWLD) values of the model group were significantly increased (P<0.001),and the time spent in the CPA-paired compartment was considerably decreased compared with the control group (P<0.001).After EA intervention for 3 and 7 days, the PWLD levels of both EA and AEA groups were apparently decreased(P<0.05),and the time spent in the CPA-paired compartment was apparently increased in the EA and AEA groups(P<0.05),suggesting a pain relief and an improvement of the negative affection after EA intervention. Additionally, following EA, the apparently-decreased expression levels of GABAAß 2,GABAB 1,PSD-95,Piccolo genes and the reduced numbers of GABAB 2 positive cells and NMDA-NR 1 mRNA as well as mGluR 1 positive fiber numbers were remarkably increased in the EA group (P<0.05, P<0.001).The expression levels of Piccolo gene, GABAB 2 and mGluR 1 positive cells/fiber numbers were apparently lower in the AEA group than in the EA group (P<0.001). No significant differences were found between the EA and AEA groups in the PWLD, time spent in the CPA-paired compartment, and the expression levels of NMDA-NR 1, GABAAß 2, GABAB 1 and PSD-95 genes (P>0.05). CONCLUSIONS: Repeated EA stimulation of ST 36-GB 34 has a role in relieving both sensory and affection dimensions of chronic pain in CNPPNA rats, which Feb be respectively related to its effects in up-regulating the expression of GABAAß 2, GABAB 1, NMDA-NR 1, PSD-95 and Piccolo genes, and in promoting the expression of mGluR 1 and GABAB 2 proteins and Piccolo gene in the amygdala.

[Effects of Electroacupuncture on Activities of Satellite Glial Cells of Dorsal Root Ganglia in Rats with Neck Incision Pain].

OBJECTIVE: To observe the effect of electroacupuncture (EA) stimulation of "Futu"(LI 18), etc. on activities of satellite glial cells (SGCs) in the dorsal root ganglia (DRG) in rats with neck-incision pain so as to explore its mechanism underlying reduction of post-surgical pain of thyroidectomy. METHODS: Male SD rats were randomly divided into control, model, EA-Futu (LI 18), EA-Hegu (LI 4)-Neiguan (PC 6), and EA-Zusanli (ST 36)-Yanglingquan (GB 34) groups, with 20 rats in each group. The neck-incision pain model was established by making a longitudinal incision and repeated mechanical stimulation. In the EA-LI 18, EA-LI 4-PC 6 and EA-ST 36-GB 34 groups, EA stimulation was administrated for 30 min, once a day,continuously for 3 days. The thermal pain threshold (PT) of the neck-incision region was detected. The immunoactivity of glial fibrillary acidic protein (GFAP,a specific marker for SGCs) and connexin 43 (Cx 43) of DRGs (C 2-C 6) was determined by fluorescent immunohistochemistry. The expression levels of GFAP, IL-1 ß, IL-6, and TNF-α mRNAs were determined by quantitative Real-time PCR, and the contents of IL-1 ß,IL-6,TNF-α assayed by enzyme linked immunosorbent assay (ELISA) and the expression of Cx 43 protein was detected by Western blot. RESULTS: After EA intervention at LI 18 and LI 4-PC 6 (but not ST 36-GB 34), neck incision-induced reduction of the thermal PT was obviously prolonged in comparison with the model group (P<0.05),suggesting a pain relief. The expression levels of GFAP, IL-1 ß, IL-6 and TNF-α mRNAs and Cx 43 protein, and the contents of IL-1 ß, IL-6 and TNF-α in C 2-C 6 DRGs were all significantly up-regulated in the model group relevant to those of the control group (P<0.05). Following EA, modeling induced dramatic increase of expression of GFAP, IL-1 ß, IL-6 and TNF-α mRNAs and Cx 43 protein in both EA-LI 18 and EA-LI 4-PC 6 groups, and the contents of IL-1 ß and TNF-α in the EA-LI 18 group, IL-6 in the EA-LI 4-PC 6 group was considerably down-regulated (P<0.05). In comparison with the model group, no significant changes were found in all the abovementioned indexes of EA-ST 36 -GB 34 group except the down-regulated IL-1 ß and TNF-α mRNAs, in the contents of IL-1 ß and TNF-α of the EA-LI 4-PC 6 group, and in the IL-6 content of the EA-LI 18 group (P>0.05). CONCLUSIONS: EA stimulation of LI 18 and LI 4-PC 6 can significantly suppress pain reaction of neck incision in the rat, which is closely associated with its effects in down-regulating the activity of SGCs, decreasing the release of pro-inflammatory cytokines and in weakening the expression of Cx 43 in the cervical DRGs.

[Clinical Trials for Thyroidectomy Under Acupuncture-aided Anesthesia by Using Electroacupuncture or Transcutaneous Acupoint Electrical Stimulation of Different Acupoints].

OBJECTIVE: To observe the effectiveness of transcutaneous acupoint electrical stimulation (TAES) or electroacupuncture (EA) stimulation of different acupoints in combination with anesthetics in the management of thyroidectomy patients, so as to choose a better stimulating method and most effective acupoints for thyroidectomy. METHODS: A total of 216 thyroidectomy patients (ASA Ⅰ-Ⅱ grades) with thyroid gland adenoma, thyroid cyst or thyroid nodules from 3 hospitals (3 research centers) were randomized into 6 groups, i.e., local anesthesia (LA, n=34), Futu (LI 18)-EA (n=36), Hegu (LI 4)-Neiguan (PC 6)-TAES (n=34), LI 4-PC 6-EA (n=36), Yanglingquan (GB 34)-EA (n=36) and non-acupoint (NA, about 1.5 cm latero-posterior to KI 9)-EA (n=34) groups according to the hospitalizition sequence. For patients of the LI 18-EA, LI 4-PC 6-TAES/EA, GB 34 and non-acupoint-EA groups, EA or TAES (2 Hz/100 Hz) was applied to the abovementioned bilateral acupoints or non-acupoint till the termination of the surgical operation. The surgery was conducted under anesthesia by local injection of 0.5% lidocaine and midazolam, and intravenous injection of fentanyl (for severe pain cases) 20 min after beginning of TAES or EA. The patients' scores of visual analogue scale (VAS),mean arterial pressure (MAP) and heart rate (HR) at the time-points of pre-anesthesia (T 0), skin-incision (T 1), skin flap-freeing (T 2), anterior cervical muscle traction (T 3), thyroid upper/lower-pole-sectioning (T 4/T 5), and thyroidectomy (T 6), and the dosages of the administered fentanyl and lidocaine were recorded. RESULTS: Compared with the corresponding time-points of the non-acupoint group, the VAS scores at T 1 and T 4 time-points in the LI 18-EA group and LI 4-PC 6-EA group, at T 1, T 5 and T 6 time-points in the LI 4-PC 6-TAES group were significantly lower (P<0.05). Compared with the corresponding time-points of the LA group, the VAS scores at T 2, T 3, T 5 and T 6 time-points in the LI 18-EA group and LI 4-PC 6-EA group, at T 3, T 5 and T 6 in the LI 4-PC 6-TAES group, and the MAP levels at T 2, T 3, T 4 and T 6 time-points in the LI 18-EA group, at T 3, T 4 in the LI 4-PC 6-EA group, at T 3, T 4, T 6 in the LI 4-PC 6 TAES group, as well as the HR levels at T 4, T 5 and T 6 in the LI 18-EA group, and at T 5, T 6 in the LI 4-PC 6-TAES group were significantly lower (P<0.05). The dosages of fentanyl in the LI 18-EA and LI 4-PC 6-TAES groups, and those of lidocaine in the LI 18-EA, LI 4-PC 6-EA and TAES groups were significantly lower relevant to the LA group and non-acupoint group (P<0.05). No significant differences were found between the LA and GB 34-EA groups, and between the LA and non-acupoint groups, as well as between the LI 4-PC 6-EA and LI 4-PC 6-TAES groups in the VAS scores, the MAP and HR levels, the dosages of lidocaine and fentanyl consumption (P>0.05). CONCLUSIONS: EA stimulation of both LI 18 and LI 4-PC 6 and TAES of LI 4-PC 6 combined with anesthetics have a better effect in inducing analgesia and controlling MAP and HR, and need lower dosages of anesthetics for patients undergoing thyroidectomy, for which LI 18 and LI 4-PC 6 are evidently superior to GB 34 and non-acupoint. Hence, combined EA or TAES and anesthetics is highly recommended for thyroidectomy.

Effect of electroacupuncture on thermal pain threshold and expression of calcitonin-gene related peptide, substance P and γ-aminobutyric acid in the cervical dorsal root ganglion of rats with incisional neck pain.

OBJECTIVE: Acupuncture therapy effectively reduces post-surgical pain, but its mechanism of action remains unclear. The aim of this study was to investigate whether expression of γ-aminobutyric acid (GABA) and the neuropeptides substance P (SP) and calcitonin gene-related peptide (CGRP) in the primary sensory neurons of cervical dorsal root ganglia (DRG) are involved in electroacupuncture (EA)-induced analgesia in a rat model of incisional neck pain. METHODS: The pain model was established by making a longitudinal midline neck incision in 60 rats. Another 15 rats underwent sham surgery (normal group). Post-incision, 15 rats remained untreated (model group) and 45 rats underwent EA (frequency 2/100 Hz, intensity 1 mA) at bilateral LI18, LI4-PC6 or ST36-GB34 (n=15 each) for 30 min at 4 hours, 24 hours, and 48 hours post-surgery, followed by thermal pain threshold (PT) measurement. 30 min later, the rats were euthanased and cervical (C3-6) DRGs removed for measurement of immunoreactivity and mRNA expression of SP/CGRP and the GABAergic neuronal marker glutamic acid decarboxylase 67 (GAD67). RESULTS: Thermal PT was significantly lower in the model group versus the normal group and increased in the LI18 and LI4-PC6 groups but not the ST36-GB34 group compared with the model group. Additionally, EA at LI18 and LI4-PC6 markedly suppressed neck incision-induced upregulation of mRNA/protein expression of SP/CGRP, and upregulated mRNA/protein expression of GAD67 in the DRGs of C3-6 segments. CONCLUSIONS: EA at LI18/LI4-PC6 increases PT in rats with incisional neck pain, which is likely related to downregulation of pronociceptive mediators SP/CGRP and upregulation of the inhibitory transmitter GABA in the primary sensory neurons of cervical DRGs.

Activation of hippocampal MEK1 contributes to the cumulative antinociceptive effect of electroacupuncture in neuropathic pain rats.

BACKGROUND: Electroacupuncture (EA) intervention can relieve a variety of pain; however, optimal EA protocols have not been clearly determined. In addition, although central mitogen-activated protein kinase kinase (MEK) signaling has been shown to be involved in the antinociceptive effect of acupuncture stimulation, its characteristics at different time-points of EA intervention have not been fully elucidated. Therefore, the present study investigated the relationship between the effects of different numbers of EA intervention sessions and the activation of MEK1 in the hippocampus and hypothalamus in a rat model of neuropathic pain. METHODS: After ligation of the left sciatic nerve, which induces chronic constriction injury (CCI), the acupoints Zusanli (ST36) and Yanglingquan (GB34) were applied. The thermal withdrawal latency of the hind paw was used to evaluate the effect of EA on pain thresholds. Intra-hippocampus microinjection of PD98059, a MEK inhibitor, was performed to validate the involvement of MEK in EA analgesia. The hippocampus and hypothalamus were harvested to examine the phosphorylation levels of MEK (pMEK) by western blotting. RESULTS: In CCI rats, the thermal pain threshold of the affected hind paw decreased significantly relative to the control. Following subsequent daily EA interventions, CCI-induced ipsilateral hyperalgesia was markedly improved from day 4 and the analgesic effect of EA lasted 3 days after cessation of EA. Four sessions of EA markedly suppressed CCI-induced decrease of hippocampal pMEK1 (normalized to the total MEK level). In contrast, successive sessions of EA intervention gradually down-regulated the CCI-induced up-regulation of hypothalamic pMEK1 along with the increase numbers of EA intervention. However, EA did not exert the same analgesic effect after microinjection of PD98059 into the contralateral hippocampus during the first 3 days of EA intervention. CONCLUSIONS: EA intervention can induce time-dependent cumulative analgesia in neuropathic pain rats after 4 successive sessions of daily EA intervention, which is at least in part related to the activation of hippocampal MEK1.

Electroacupuncture Reduces the Effects of Acute Noxious Stimulation on the Electrical Activity of Pain-Related Neurons in the Hippocampus of Control and Neuropathic Pain Rats.

To study the effects of acupuncture analgesia on the hippocampus, we observed the effects of electroacupuncture (EA) and mitogen-activated protein kinase (MEK) inhibitor on pain-excited neurons (PENs) and pain-inhibited neurons (PINs) in the hippocampal area CA1 of sham or chronic constrictive injury (CCI) rats. The animals were randomly divided into a control, a CCI, and a U0126 (MEK1/2 inhibitor) group. In all experiments, we briefly (10-second duration) stimulated the sciatic nerve electrically and recorded the firing rates of PENs and PINs. The results showed that in both sham and CCI rats brief sciatic nerve stimulation significantly increased the electrical activity of PENs and markedly decreased the electrical activity of PINs. These effects were significantly greater in CCI rats compared to sham rats. EA treatment reduced the effects of the noxious stimulus on PENs and PINs in both sham and CCI rats. The effects of EA treatment could be inhibited by U0126 in sham-operated rats. The results suggest that EA reduces effects of acute sciatic nerve stimulation on PENs and PINs in the CA1 region of the hippocampus of both sham and CCI rats and that the ERK (extracellular regulated kinase) signaling pathway is involved in the modulation of EA analgesia.

[Effect of Electroacupuncture Intervention on Expression of Pain Sensory and Affective Proce- ssing-related µ-opioid Receptor, etc. in the Amygdala in Chronic Neuropathy Pain Rats].

OBJECTIVE: To observe the effect of electroacupuncture (EA) on expression of pain sensory and affective processing-related µ-opioid receptor (MOR), glutamatergic AMPA receptor subunit GIuA 1, extracellular signal-regulated kinase (ERK 1/2), cAMP response element binding protein(CREB) in the amygdala in chronic constrictive injury (CC) + negative affection(NA) rats, so as to reveal its mechanism underlying pain relief. METHODS: A total of 32 male Wistar rats were randomized into normal control, model, EA, and anesthesia+ EA (AEA) groups (n = 8 in each group). The neuropathic pain NA model was established by ligation of the left sciatic nerve and repeated electrical stimulation of the paw-bottom in the pain-paired compartment. EA was applied to bilateral "Zusanli" (ST 36) and "Yanglingquan" (GB 34) for 30 min, once daily for 7 days. Thermal pain threshold (paw withdrawl latency, PWL) of the bilateral paws was measured by using a Tail-Flick Unit. The expression levels of MOR and p-CREB in the central amygdala (CeA) and those of MOR, GluA 1, p-ERK 1/2 and p-CREB in the right amygdala area were determined using immunofluorescence and Western blot, respectively. RESULTS: in comparison with the normal group, PWL difference (PWLD) values of the model group were significantly increased (P < 0.001), and the time spent in the CPA-paired. compartment was considerably decreased (P < 0.001). After EA, the PWLD levels of both EA and AEA groups were apparently decreased (P < 0.05), showing a pain relief; and the time spent in the CPA-paired compartment was apparently increased in the EA group (P < 0.05) , rather than in the AEA group (P > 0.05). Additionally , compared to the normal group, the expression level of MOR protein in the amygdala was remarkably increased (P < 0.05) and those of GIuA 1, p-ERK 2 and p-CREB proteins were apparently decreased (P < 0.05). After EA intervention for 7 days, the expression levels of these four proteins in the EA group, and those of MOR, p-ERK 2 and p-CREB in the AEA group were significantly up-regulated (P < 0.001, P < 0.01, P < 0.05). The expression level of GIuA 1 was significantly higher in the EA group than in the AEA group (P < 0.05). CONCLUSION: Repeated EA stimulation of ST 36-GB 34 has a definite effect in relieving both sensation and affection dimensions of pain in NA rats, which may be related to its effect in up-regulating the expression of GIuA 1 in the amygdala, but the effects of MOR, p-ERK 2 and p-CREB need being researched further.

Involvement of hippocampal acetylcholinergic receptors in electroacupuncture analgesia in neuropathic pain rats.

BACKGROUND: Cumulating evidence has shown a close correlation between electroacupuncture stimulation (EAS) frequency-specific analgesic effect and central opioid peptides. However, the actions of hippocampal acetylcholinergic receptors have not been determined. This study aims to observe the effect of different frequencies of EAS on the expression of hippocampal muscarinic and nicotinic acetylcholinergic receptors (mAChRs, nAChRs) in neuropathic pain rats for revealing their relationship. METHODS: Forty male Wistar rats were randomly and equally divided into sham, CCI model, 2, 2/15 and 100 HzEA groups. The neuropathic pain model was established by ligature of the left sciatic nerve to induce chronic constriction injury (CCI). EAS was applied to bilateral Zusanli (ST36) and Yanglingquan (GB34) for 30 min, once daily for 14 days except weekends. The mechanical pain thresholds (withdrawal latencies, PWLs) of bilateral hindpaws were measured. The expression levels of hippocampal M1 and M2 mAChR, and α4 and ß2 nAChR genes and proteins were detected by quantitative RT-PCR and Western blot, separately. The involvement of mAChR and nAChR in the analgesic effect of EAS was confirmed by intra-hippocampal microinjection of M1mAChR antagonist (Pirenzepine) and α4ß2 nAChR antagonist (dihydro-beta-erythroidine) respectively. RESULTS: Following EAS, the CCI-induced increase of difference values of bilateral PWLs on day 6 and 14 was significantly reduced (P < 0.05), with 2/15 Hz being greater than 100 Hz EAS on day 14 (P < 0.05). After 2 weeks' EAS, the decreased expression levels of M1 mAChR mRNA of both 2 and 2/15 Hz groups and M1 mAChR protein of the three EAS groups, α4 AChR mRNA of the 2/15 Hz group and ß2 nAChR protein of the three EAS groups were considerably increased (P < 0.05), suggesting an involvement of M1 mAChR and ß2 nAChR proteins in EAS-induced pain relief. No significant changes were found in the expression of M2 mAChR mRNA and protein, α4 nAChR protein and ß2 nAChR mRNA after CCI and EAS (P > 0.05). The analgesic effect of EAS was abolished by intra-hippocampal microinjection of M1mAChR and α4ß2 nAChR antagonists respectively. CONCLUSIONS: EAS of ST36-GB34 produces a cumulative analgesic effect in neuropathic pain rats, which is frequency-dependent and probably mediated by hippocampal M1 mAChR and ß2 nAChR proteins.

[Does the Nucleus Ambiguus-Vague Nerve Mediate Anti-myocardial Ischemic Effect of Electroacupuncture of "Neiguan" (PC 6)-"Jianshi" (PC 7) in Myocardial Ischemia Rats].

OBJECTIVE: To observe the effect of electroacupuncture (EA) stimulation of "Neiguan" (PC 6)-"Jianshi" (PC 7) on ischemic myocardial injury in myocardial ischemic (MI) rats, so as to explore its mechanism underlying improvement of MI. METHODS: A total of 48 male Wistar rats were randomly divided into normal, MI model, PC 6-PC 7, Sanyinjiao-Diji (SP 6-SP 8) groups (n=8 in each group for physiological experiments, n=4 in each group for immunoflorescence stain). The MI model was established by occlusion of the anterior descending branch of the left coronary artery. Electrocardiogram (ECG) of the neck-thoracic lead was recorded and the heart rate variability (HRV) analyzed by using a physiological signal collecting system (MP 150) and PowerLab software. EA (2 Hz/15 Hz, 0.5 mA) was applied to bilateral PC 6-PC 7 or SP 6-SP 8 for 30 min every time, on the 1,2,3 day after modeling. Serum creatine kinase-MB isoenzyme (CK-MB) and lactate dehydrogenase-1 (LDH 1) and endothelin (ET) contents were assayed by ELISA. The expression of choline acetyltransferase (ChAT) and vesicular acetylcholine transporter (VAChT) and c-fos proteins in the nucleus ambiguus (NA) region of the medulla oblongata was detected by immunofluo-rescence stain. RESULTS: Compared with the normal group, the ECG J-point height (1 h), serum CK-MB, LDH 1 and ET contents (1 d and 3 d), HR (1 h and 1 d) and LF/HF levels of HRV (1 h, 1 d and 3 d) and the number of c-fos positive neurons (3 d) in the NA region were significantly increased in the model group (P<0.01, P<0.05), while HF levels (1 h, 1 d and 3 d) and ECG J-point height (1 d and 3 d) were considerably decreased after MI. After EA intervention, the ECG J-point height 3 d after MI was close to zero in both PC 6-PC 7 and SP 6-SP 8 groups, being better than that (negative value) of the model group, and serum CK-MB, LDH 1 and ET contents (1 d, 3 d) of both EA groups, and HR (1 d) and LF/HF (3 d) of the PC 6-PC 7 group were obviously down-regulated (P<0.01, P<0.05), and the decreased HF 3 d post-MI and the increased number of c-fos positive neurons were significantly up-regulated in the PC 6-PC 7 group (P<0.01). No significant differences were found between the two EA groups in raising J-point height and in down-regulating serum CK-MB, LDH 1 and ET contents (P>0.05). Compared with the model group, no significant changes were found in HR 1 d post-MI of the SP 6-SP 8 group, 3 d post-MI of both EA groups, in HF 3 d post-MI of the SP 6-SP 8 group, in LF/HF 1 d post-MI of both EA groups and 3 d post-MI of the SP 6-SP 8 group, in the number of c-fos positive neurons of the SP 6-SP 8 group, and ChAT and VAChT positive neurons of both EA groups (P>0.05). CONCLUSIONS: EA intervention may improve ischemic myocardial injury in MI rats, probably by activating neurons in the NA region, and enhancing the cardiac parasympathetic tension, and balancing cardiac sympathetic/parasympathetic nerve activities, but the effect of cholinergic neurons of NA needs being studied further.

Effect of Repeated Electroacupuncture Intervention on Hippocampal ERK and p38MAPK Signaling in Neuropathic Pain Rats.

Results of our past studies showed that hippocampal muscarinic acetylcholine receptor (mAChR)-1 mRNA and differentially expressed proteins participating in MAPK signaling were involved in electroacupuncture (EA) induced cumulative analgesia in neuropathic pain rats, but the underlying intracellular mechanism remains unknown. The present study was designed to observe the effect of EA stimulation (EAS) on hippocampal extracellular signal-regulated kinases (ERK) and p38 MAPK signaling in rats with chronic constrictive injury (CCI) of the sciatic nerve, so as to reveal its related intracellular targets in pain relief. After CCI, the thermal pain thresholds of the affected hind were significantly decreased compared with the control group (P < 0.05). Following one and two weeks' EAS of ST 36-GB34, the pain thresholds were significantly upregulated (P < 0.05), and the effect of EA2W was remarkably superior to that of EA2D and EA1W (P < 0.05). Correspondingly, CCI-induced decreased expression levels of Ras, c-Raf, ERK1 and p-ERK1/2 proteins, and p38 MAPK mRNA and p-p38MAPK protein in the hippocampus tissues were reversed by EA2W (P < 0.05). The above mentioned results indicated that EA2W induced cumulative analgesic effect may be closely associated with its function in removing neuropathic pain induced suppression of intracellular ERK and p38MAPK signaling in the hippocampus.