Objective:To evaluate the role of cannabinoid receptor 1 (CB1) in the spinal membrane in electroacupuncture (EA)-induced alleviation of morphine-triggered opioid-induced hyperalgesia (OIH) and the relationship with phosphorylated extracellular signal-regulated kinase 1/2 (p-ERK1/2) in rats.Methods:Forty-eight clean-grade healthy male Sprague-Dawley rats, aged 2-3 months, weighing 240-260 g, in which intrathecal catheters were successfully implanted, were divided into 4 groups ( n=12 each) using a random number table method: normal saline group (NS group), morphine group (M group), morphine+ EA group (ME group), and morphine+ EA+ CB1 antagonist group (MEA group). The OIH model was established by intrathecal injection of morphine 15 μg (10 μl) twice a day for 7 consecutive days. The equal volume of normal saline 10 μl was given instead in NS group. EA of the " Yanglingquan" (GB34) and " Zusanli" (ST36) acupoints lasting 30 min was performed after the first administration of medication each day, with a current intensity of 2 mA and frequency of 2 Hz in ME group. In MEA group, morphine (15 μg) and CB1 antagonist AM251 30 μg (10 μl) were intrathecally injected twice a day for 7 consecutive days, with other treatments similar to those previously described in ME group. The mechanical paw withdrawal threshold (MWT) and thermal paw withdrawal latency (TWL) were measured at 1 day before administration (T 0) and on days 1, 3, 5 and 7 after administration (T 1-4). Rats were deeply anesthetized and sacrificed at T 3, 4 after administration, and the L 4-6 spinal cord tissues were collected for determination of the expression of membrane CB1, ERK1/2 and p-ERK1/2 by Western blot. Results:Compared with NS group, the MWT was significantly decreased and the TWL was shortened at T 3, 4 in M, ME and MEA groups, the expression of spinal membrane CB1 and p-ERK1/2 was significantly up-regulated at T 4 after administration in M group, and the expression of spinal membrane CB1 was significantly up-regulated at T 3, 4 after administration in ME and MEA groups ( P<0.05). Compared with M group, the MWT was significantly increased and the TWL was prolonged at T 3, 4, and the expression of p-ERK1/2 was down-regulated at T 4 after administration in ME group ( P<0.05), no significant change was found in MWT or TWL at T 3, 4 in MEA group ( P>0.05), and the expression of spinal membrane CB1 was significantly up-regulated at T 3, 4 after administration in ME and MEA groups ( P<0.05). Compared with ME group, the MWT was significantly decreased and the TWL was shortened at T 3, 4, and the expression of spinal membrane CB1 and p-ERK1/2 was up-regulated at T 4 after administration in MEA group ( P<0.05). Conclusions:Up-regulation of spinal membrane CB1 expression is involved in EA-mediated alleviation of morphine-induced OIH, which is associated with the inhibition of ERK1/2 phosphorylation in rats.

Objective:To compare the clinical efficacy of percutaneous endoscopic interlaminar discectomy (PEID) and posterior small incision microdiscectomy (MD) in the treatment of recurrent lumbar disc herniation.Methods:A retrospective analysis was conducted on the data of 132 patients who underwent revision surgery for recurrent lumbar disc herniation at the same segment at Qilu Hospital of Shandong University between July 2012 and August 2022. The patients were treated with either PEID or MD. The PEID group consisted of 90 patients, including 51 males and 39 females, with a mean age of 42.7±11.3 years and a mean body mass index (BMI) of 23.7±3.4 kg/m 2. The surgical segments were L 4-5 in 38 cases and L 5S 1 in 52 cases. The primary surgeries included open discectomy in 7 cases, laminectomy with bone graft in 3 cases, MD in 35 cases, and PEID in 45 cases. The MD group consisted of 42 patients, including 30 males and 12 females, with a mean age of 41.2±12.6 years and a mean BMI of 24.3±4.7 kg/m 2. The surgical segments were L 4-5 in 19 cases and L 5S 1 in 23 cases. The primary surgeries included open discectomy in 2 cases, laminectomy with bone graft in 1 case, MD in 17 cases, and PEID in 22 cases. The visual analogue scale (VAS) scores for low back pain and leg pain, Oswestry disability index (ODI), immediate postoperative VAS score for surgical wound pain, intraoperative blood loss, surgical wound length, operation duration, length of hospital stay, and various complications before and after surgery were compared between the PEID and MD groups. Results:The operation duration in the PEID group was 81.7±11.3 min, that in the MD group was 85.2±9.5 min, but the difference was not statistically significant ( t=1.740, P=0.081). The intraoperative blood loss in the PEID group was 4.4±2.9 ml, the surgical wound length was 0.9±0.2 cm, and the length of hospital stay was 3.1±1.3 d, all significantly less than those in the MD group (26.6±10.3 ml, 3.4±1.1 cm, and 8.7±1.6 d, respectively), with statistically significant differences ( P<0.05). Both groups were followed up, with a mean follow-up duration of 24.4±5.5 months in the PEID group and 24.5±4.9 months in the MD group, and there was no statistically significant difference between the two groups ( t=0.101, P=0.920). Both the PEID and MD groups showed significant improvements in postoperative VAS scores for leg pain, VAS scores for low back pain, and ODI compared with preoperative values ( P<0.05). Additionally, the VAS score for surgical wound pain on the first postoperative day in the PEID group was 1.2±0.4, which was lower than that in the MD group (2.9±0.6), with a statistically significant difference ( t=19.261, P<0.001). The incidence rates of muscle weakness, postoperative sensory abnormalities, and dural tears in the PEID group were 12%(11/90), 27%(24/90), and 6%(5/90), respectively, significantly lower than those in the MD group [31%(13/42), 40%(17/42), and 33%(14/42), respectively], with statistically significant differences ( P<0.05). However, there were no statistically significant differences between the two groups in the incidence rates of recurrence, residual nucleus pulposus, spinal cord-like hypertension syndrome, subcutaneous wound infection, or intervertebral space infection ( P>0.05). No patients in either group developed retroperitoneal hematoma postoperatively. Conclusion:For patients with recurrent lumbar disc herniation after primary posterior surgery, PEID demonstrates equally excellent clinical efficacy compared with MD, with smaller surgical trauma and a lower incidence of complications.

Metabolic dysfunction-associated steatotic liver disease (MASLD), the most prevalent chronic liver condition globally, lacks adequate and effective therapeutic remedies in clinical practice. Recent studies have increasingly highlighted the close connection between the ubiquitin-proteasome system (UPS) and the progression of MASLD. This relationship is crucial for understanding the disease's underlying mechanism. As a sophisticated process, the UPS govern protein stability and function, maintaining protein homeostasis, thus influencing a multitude of elements and biological events of eukaryotic cells. It comprises four enzyme families, namely, ubiquitin-activating enzymes (E1), ubiquitin-conjugating enzymes (E2), ubiquitin-protein ligases (E3), and deubiquitinating enzymes (DUBs). This review aims to delve into the array of pathways and therapeutic targets implicated in the ubiquitination within the pathogenesis of MASLD. Therefore, this review unveils the role of ubiquitination in MASLD while spotlighting potential therapeutic targets within the context of this disease.

Objective:To evaluate the role of ZIP7 in sepsis-induced cardiomyopathy in mice.Methods:Ninety wild-type and 90 cardiomyocyte-specific knockout ZIP7 (ZIP7 cKO) male C57BL/6 mice, aged 6-8 weeks, weighing 20-25 g, were divided into 2 groups using a random number table method: wild-type sham operation group (Sham group) and wild-type sepsis group (Sep group), ZIP7 cKO sham operation group (cKO + Sham group) and ZIP7 cKO sepsis group (cKO + Sep group), with 45 mice in each group. The sepsis-induced cardiomyopathy model was developed using the cecal ligation and puncture in anesthetized mice. Twenty mice were randomly selected to record the survival for 10 days postoperatively. At 18 h after surgery, the left ventricular ejection fraction (LVEF) and fractional shortening (LVFS) were measured by echocardiography, and serum concentrations of cardiac troponin T (cTnT), tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6) were measured by enzyme-linked immunosorbent assay. The contents of hydroxyl radical (·OH) and peroxynitrite anion (ONOO -) were determined using a colorimetric assay, the morphology of myocardial mitochondria was observed with a transmission electron microscope, and the expression of dynamin-related protein 1 (Drp1), mitofusin-2 (Mfn2), and optic atrophy 1 (Opa1) in myocardial tissues was detected using Western blot. Results:Compared to Sham group, the survival rate, LVEF and LVFS were significantly decreased, serum concentrations of cTnT, TNF-α and IL-6 were increased, the contents of ·OH and ONOO - in myocardial tissues were increased, the expression of Drp1 was up-regulated, the expression of Mfn2 and Opa1 was down-regulated ( P<0.05), myocardial cells exhibited mitochondrial swelling, and marked destruction of mitochondrial cristae was observed in Sep group, and no significant differences were found in the aforementioned parameters in cKO+ Sham group ( P>0.05). Compared to Sep group, the survival rate, LVEF and LVFS were significantly increased, serum concentrations of cTnT, TNF-α and IL-6 were decreased, the contents of ·OH and ONOO - in myocardial tissues were decreased, the expression of Drp1 was down-regulated, the expression of Mfn2 and Opa1 was up-regulated ( P<0.05), and mitochondrial swelling in myocardial cells was mild, with less dissolution and destruction of mitochondrial cristae in cKO+ Sep group. Conclusions:Myocardial ZIP7 can promote mitochondrial fusion and inhibit mitochondrial fission, potentially contributing to the mechanism of sepsis-induced cardiomyopathy in mice.

Objective:To evaluate the role of tubulin tyrosin ligase like-6 (TTLL6)-mediated microtubule polyglutamylation and Spastin(a microtubule cleaving protein)-induced excessive microtubule cleavage in the developmental impairment of dendritic spines in neonatal mice following repeated sevoflurane anesthesia, by utilizing TTLL6 conditional knockout mice.Methods:Fifty SPF female TTLL6 brain tissue-specific knockout (TTLL6 CKO: Camk2-Cre + ; TTLL6 f/f) and fifty control (TTLL6 CON: TTLL6 f/f) mice with C57BL/6J background, aged 6 days old were selected.TTLL6 CKO mice were divided into TTLL6 CON control group and TTLL6 CON sevoflurane group, and TTLL6 CKO mice were divided into TTLL6 CKO control group and TTLL6 CKO sevoflurane group, with 25 mice in each group by random block method.Mice in the sevoflurane groups were exposed to 3% sevoflurane with 60% O 2 for 2 hours daily on postnatal days 6, 8, and 10.The mice in control groups received only 60% O 2 under the same condition.The polyGlu-Tubulin and postsynaptic density 95(PSD95) protein expression were detected using Western blot. The expressions of TTLL6, Spastin, and α-Tubulin were assessed via immunofluorescence.Golgi staining and electron microscopy were employed to observe the density of hippocampal dendritic spines and synaptic conditions. The Morris water maze test was used to evaluate spatial memory capabilities. Statistical analysis was performed using GraphPad Prism 8.0 software. Results:(1) Behavioral results showed significant time and group interactions among the four groups in terms of latency to find the platform ( F=8.22, P<0.001).Mice in the TTLL6 CON sevoflurane group had a significantly longer escape latency on days 3-7 compared with the TTLL6 CON control group (all P<0.05), while there was no significant difference between the TTLL6 CKO sevoflurane group and the TTLL6 CKO control group (all P>0.05). The number of platform crossings differed significantly among the four groups ( H=11.95, P=0.007).The TTLL6 CON sevoflurane group had significantly fewer crossing times than the TTLL6 CON control group ( P<0.05), but no significant difference was observed between the TTLL6 CKO sevoflurane group and the TTLL6 CKO control group ( P>0.05). (2) Golgi staining and electron microscopy results revealed significant differences in dendritic spine density and synapse number among the four groups( F=29.00, 41.94, both P<0.001). The dendritic spine density ((5.83±0.40)/10 μm) and the number of synapses ((3.67±0.58)/10 μm) in the TTLL6 CON sevoflurane group were both significantly lower than those in the TTLL6 CON control group ((12.87±1.70)/10 μm, (9.33±0.57)/10 μm)(both P<0.05). In contrast, there was no statistically significant difference between the TTLL6 CKO sevoflurane group and TTLL6 CKO control group (both P>0.05). (3) Immunofluorescence results showed significant differences in the percentage of TTLL6 and Spastin and α-Tubulin co-expressed positive cells in the CA3 region of the hippocampus among the four groups of mice ( F=215.20, 26.08, both P<0.001). The percentage of TTLL6 and Spastin and α-Tubulin co-expressed positive cells in the TTLL6 CON sevoflurane group ((16.75±1.81) %, (47.98±8.42) %) were significantly higher than those in the TTLL6 CON control group ((2.44±0.58) %, (20.07±4.54) %)(both P<0.05), while there was no statistically significant difference between the TTLL6 CKO sevoflurane group and TTLL6 CKO control group ( P>0.05). (4) Western blot results indicated significant differences in the expression of polyGlu-Tubulin and PSD95 proteins in the hippocampal tissue among the four groups of mice ( F=19.66, 8.57, both P<0.001). The TTLL6 CON sevoflurane group had higher polyGlu-Tubulin expression (0.86±0.19) and lower PSD95 expression (0.61±0.13) compared to the TTLL6 CON control group (0.51±0.11, 1.01±0.07) (both P<0.05).However, there was no significant difference between the TTLL6 CKO sevoflurane group and the TTLL6 CKO control group ( P>0.05). Conclusion:The mechanism underlying long-term cognitive impairment in developing brain of neonatal mice caused by repeated sevoflurane anesthesia may relate to the upregulation of TTLL6-induced microtubule polyglutamylation and accelerated Spastin-mediated microtubule severing, which ultimately leads to abnormal dendritic spine development.

In this study,the similarities and differences of plasma collection and quality control in China and abroad were analyzed by comparing the related regulations,standards,guidelines and literatures.Rational and constructive suggestions were proposed,aiming to optimize domestic plasma management and promote the improvement of plasma-related standards.There was little difference on facilities and safety control process of plasma between China and the developed countries(United States,EU and Japan),However,significant differences existed on plasma station setting,donor screening standards,collection interval,volume limits,plasma testing modes and tests,plasma quarantine standard and utilization of recovered plasma.The United States sets the industry benchmark and is worthy of reference for our country both in plasma collection and quality control.

Objective:To evaluate the role of tubulin tyrosin ligase like-6 (TTLL6)-mediated microtubule polyglutamylation and Spastin(a microtubule cleaving protein)-induced excessive microtubule cleavage in the developmental impairment of dendritic spines in neonatal mice following repeated sevoflurane anesthesia, by utilizing TTLL6 conditional knockout mice.Methods:Fifty SPF female TTLL6 brain tissue-specific knockout (TTLL6 CKO: Camk2-Cre + ; TTLL6 f/f) and fifty control (TTLL6 CON: TTLL6 f/f) mice with C57BL/6J background, aged 6 days old were selected.TTLL6 CKO mice were divided into TTLL6 CON control group and TTLL6 CON sevoflurane group, and TTLL6 CKO mice were divided into TTLL6 CKO control group and TTLL6 CKO sevoflurane group, with 25 mice in each group by random block method.Mice in the sevoflurane groups were exposed to 3% sevoflurane with 60% O 2 for 2 hours daily on postnatal days 6, 8, and 10.The mice in control groups received only 60% O 2 under the same condition.The polyGlu-Tubulin and postsynaptic density 95(PSD95) protein expression were detected using Western blot. The expressions of TTLL6, Spastin, and α-Tubulin were assessed via immunofluorescence.Golgi staining and electron microscopy were employed to observe the density of hippocampal dendritic spines and synaptic conditions. The Morris water maze test was used to evaluate spatial memory capabilities. Statistical analysis was performed using GraphPad Prism 8.0 software. Results:(1) Behavioral results showed significant time and group interactions among the four groups in terms of latency to find the platform ( F=8.22, P<0.001).Mice in the TTLL6 CON sevoflurane group had a significantly longer escape latency on days 3-7 compared with the TTLL6 CON control group (all P<0.05), while there was no significant difference between the TTLL6 CKO sevoflurane group and the TTLL6 CKO control group (all P>0.05). The number of platform crossings differed significantly among the four groups ( H=11.95, P=0.007).The TTLL6 CON sevoflurane group had significantly fewer crossing times than the TTLL6 CON control group ( P<0.05), but no significant difference was observed between the TTLL6 CKO sevoflurane group and the TTLL6 CKO control group ( P>0.05). (2) Golgi staining and electron microscopy results revealed significant differences in dendritic spine density and synapse number among the four groups( F=29.00, 41.94, both P<0.001). The dendritic spine density ((5.83±0.40)/10 μm) and the number of synapses ((3.67±0.58)/10 μm) in the TTLL6 CON sevoflurane group were both significantly lower than those in the TTLL6 CON control group ((12.87±1.70)/10 μm, (9.33±0.57)/10 μm)(both P<0.05). In contrast, there was no statistically significant difference between the TTLL6 CKO sevoflurane group and TTLL6 CKO control group (both P>0.05). (3) Immunofluorescence results showed significant differences in the percentage of TTLL6 and Spastin and α-Tubulin co-expressed positive cells in the CA3 region of the hippocampus among the four groups of mice ( F=215.20, 26.08, both P<0.001). The percentage of TTLL6 and Spastin and α-Tubulin co-expressed positive cells in the TTLL6 CON sevoflurane group ((16.75±1.81) %, (47.98±8.42) %) were significantly higher than those in the TTLL6 CON control group ((2.44±0.58) %, (20.07±4.54) %)(both P<0.05), while there was no statistically significant difference between the TTLL6 CKO sevoflurane group and TTLL6 CKO control group ( P>0.05). (4) Western blot results indicated significant differences in the expression of polyGlu-Tubulin and PSD95 proteins in the hippocampal tissue among the four groups of mice ( F=19.66, 8.57, both P<0.001). The TTLL6 CON sevoflurane group had higher polyGlu-Tubulin expression (0.86±0.19) and lower PSD95 expression (0.61±0.13) compared to the TTLL6 CON control group (0.51±0.11, 1.01±0.07) (both P<0.05).However, there was no significant difference between the TTLL6 CKO sevoflurane group and the TTLL6 CKO control group ( P>0.05). Conclusion:The mechanism underlying long-term cognitive impairment in developing brain of neonatal mice caused by repeated sevoflurane anesthesia may relate to the upregulation of TTLL6-induced microtubule polyglutamylation and accelerated Spastin-mediated microtubule severing, which ultimately leads to abnormal dendritic spine development.

Objective:To compare the clinical efficacy of percutaneous endoscopic interlaminar discectomy (PEID) and posterior small incision microdiscectomy (MD) in the treatment of recurrent lumbar disc herniation.Methods:A retrospective analysis was conducted on the data of 132 patients who underwent revision surgery for recurrent lumbar disc herniation at the same segment at Qilu Hospital of Shandong University between July 2012 and August 2022. The patients were treated with either PEID or MD. The PEID group consisted of 90 patients, including 51 males and 39 females, with a mean age of 42.7±11.3 years and a mean body mass index (BMI) of 23.7±3.4 kg/m 2. The surgical segments were L 4-5 in 38 cases and L 5S 1 in 52 cases. The primary surgeries included open discectomy in 7 cases, laminectomy with bone graft in 3 cases, MD in 35 cases, and PEID in 45 cases. The MD group consisted of 42 patients, including 30 males and 12 females, with a mean age of 41.2±12.6 years and a mean BMI of 24.3±4.7 kg/m 2. The surgical segments were L 4-5 in 19 cases and L 5S 1 in 23 cases. The primary surgeries included open discectomy in 2 cases, laminectomy with bone graft in 1 case, MD in 17 cases, and PEID in 22 cases. The visual analogue scale (VAS) scores for low back pain and leg pain, Oswestry disability index (ODI), immediate postoperative VAS score for surgical wound pain, intraoperative blood loss, surgical wound length, operation duration, length of hospital stay, and various complications before and after surgery were compared between the PEID and MD groups. Results:The operation duration in the PEID group was 81.7±11.3 min, that in the MD group was 85.2±9.5 min, but the difference was not statistically significant ( t=1.740, P=0.081). The intraoperative blood loss in the PEID group was 4.4±2.9 ml, the surgical wound length was 0.9±0.2 cm, and the length of hospital stay was 3.1±1.3 d, all significantly less than those in the MD group (26.6±10.3 ml, 3.4±1.1 cm, and 8.7±1.6 d, respectively), with statistically significant differences ( P<0.05). Both groups were followed up, with a mean follow-up duration of 24.4±5.5 months in the PEID group and 24.5±4.9 months in the MD group, and there was no statistically significant difference between the two groups ( t=0.101, P=0.920). Both the PEID and MD groups showed significant improvements in postoperative VAS scores for leg pain, VAS scores for low back pain, and ODI compared with preoperative values ( P<0.05). Additionally, the VAS score for surgical wound pain on the first postoperative day in the PEID group was 1.2±0.4, which was lower than that in the MD group (2.9±0.6), with a statistically significant difference ( t=19.261, P<0.001). The incidence rates of muscle weakness, postoperative sensory abnormalities, and dural tears in the PEID group were 12%(11/90), 27%(24/90), and 6%(5/90), respectively, significantly lower than those in the MD group [31%(13/42), 40%(17/42), and 33%(14/42), respectively], with statistically significant differences ( P<0.05). However, there were no statistically significant differences between the two groups in the incidence rates of recurrence, residual nucleus pulposus, spinal cord-like hypertension syndrome, subcutaneous wound infection, or intervertebral space infection ( P>0.05). No patients in either group developed retroperitoneal hematoma postoperatively. Conclusion:For patients with recurrent lumbar disc herniation after primary posterior surgery, PEID demonstrates equally excellent clinical efficacy compared with MD, with smaller surgical trauma and a lower incidence of complications.

Objective:To evaluate the role of ZIP7 in sepsis-induced cardiomyopathy in mice.Methods:Ninety wild-type and 90 cardiomyocyte-specific knockout ZIP7 (ZIP7 cKO) male C57BL/6 mice, aged 6-8 weeks, weighing 20-25 g, were divided into 2 groups using a random number table method: wild-type sham operation group (Sham group) and wild-type sepsis group (Sep group), ZIP7 cKO sham operation group (cKO + Sham group) and ZIP7 cKO sepsis group (cKO + Sep group), with 45 mice in each group. The sepsis-induced cardiomyopathy model was developed using the cecal ligation and puncture in anesthetized mice. Twenty mice were randomly selected to record the survival for 10 days postoperatively. At 18 h after surgery, the left ventricular ejection fraction (LVEF) and fractional shortening (LVFS) were measured by echocardiography, and serum concentrations of cardiac troponin T (cTnT), tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6) were measured by enzyme-linked immunosorbent assay. The contents of hydroxyl radical (·OH) and peroxynitrite anion (ONOO -) were determined using a colorimetric assay, the morphology of myocardial mitochondria was observed with a transmission electron microscope, and the expression of dynamin-related protein 1 (Drp1), mitofusin-2 (Mfn2), and optic atrophy 1 (Opa1) in myocardial tissues was detected using Western blot. Results:Compared to Sham group, the survival rate, LVEF and LVFS were significantly decreased, serum concentrations of cTnT, TNF-α and IL-6 were increased, the contents of ·OH and ONOO - in myocardial tissues were increased, the expression of Drp1 was up-regulated, the expression of Mfn2 and Opa1 was down-regulated ( P<0.05), myocardial cells exhibited mitochondrial swelling, and marked destruction of mitochondrial cristae was observed in Sep group, and no significant differences were found in the aforementioned parameters in cKO+ Sham group ( P>0.05). Compared to Sep group, the survival rate, LVEF and LVFS were significantly increased, serum concentrations of cTnT, TNF-α and IL-6 were decreased, the contents of ·OH and ONOO - in myocardial tissues were decreased, the expression of Drp1 was down-regulated, the expression of Mfn2 and Opa1 was up-regulated ( P<0.05), and mitochondrial swelling in myocardial cells was mild, with less dissolution and destruction of mitochondrial cristae in cKO+ Sep group. Conclusions:Myocardial ZIP7 can promote mitochondrial fusion and inhibit mitochondrial fission, potentially contributing to the mechanism of sepsis-induced cardiomyopathy in mice.

Objective:To evaluate the role of cannabinoid receptor 1 (CB1) in the spinal membrane in electroacupuncture (EA)-induced alleviation of morphine-triggered opioid-induced hyperalgesia (OIH) and the relationship with phosphorylated extracellular signal-regulated kinase 1/2 (p-ERK1/2) in rats.Methods:Forty-eight clean-grade healthy male Sprague-Dawley rats, aged 2-3 months, weighing 240-260 g, in which intrathecal catheters were successfully implanted, were divided into 4 groups ( n=12 each) using a random number table method: normal saline group (NS group), morphine group (M group), morphine+ EA group (ME group), and morphine+ EA+ CB1 antagonist group (MEA group). The OIH model was established by intrathecal injection of morphine 15 μg (10 μl) twice a day for 7 consecutive days. The equal volume of normal saline 10 μl was given instead in NS group. EA of the " Yanglingquan" (GB34) and " Zusanli" (ST36) acupoints lasting 30 min was performed after the first administration of medication each day, with a current intensity of 2 mA and frequency of 2 Hz in ME group. In MEA group, morphine (15 μg) and CB1 antagonist AM251 30 μg (10 μl) were intrathecally injected twice a day for 7 consecutive days, with other treatments similar to those previously described in ME group. The mechanical paw withdrawal threshold (MWT) and thermal paw withdrawal latency (TWL) were measured at 1 day before administration (T 0) and on days 1, 3, 5 and 7 after administration (T 1-4). Rats were deeply anesthetized and sacrificed at T 3, 4 after administration, and the L 4-6 spinal cord tissues were collected for determination of the expression of membrane CB1, ERK1/2 and p-ERK1/2 by Western blot. Results:Compared with NS group, the MWT was significantly decreased and the TWL was shortened at T 3, 4 in M, ME and MEA groups, the expression of spinal membrane CB1 and p-ERK1/2 was significantly up-regulated at T 4 after administration in M group, and the expression of spinal membrane CB1 was significantly up-regulated at T 3, 4 after administration in ME and MEA groups ( P<0.05). Compared with M group, the MWT was significantly increased and the TWL was prolonged at T 3, 4, and the expression of p-ERK1/2 was down-regulated at T 4 after administration in ME group ( P<0.05), no significant change was found in MWT or TWL at T 3, 4 in MEA group ( P>0.05), and the expression of spinal membrane CB1 was significantly up-regulated at T 3, 4 after administration in ME and MEA groups ( P<0.05). Compared with ME group, the MWT was significantly decreased and the TWL was shortened at T 3, 4, and the expression of spinal membrane CB1 and p-ERK1/2 was up-regulated at T 4 after administration in MEA group ( P<0.05). Conclusions:Up-regulation of spinal membrane CB1 expression is involved in EA-mediated alleviation of morphine-induced OIH, which is associated with the inhibition of ERK1/2 phosphorylation in rats.