Schwann cell transplantation is a promising method to promote neural repair, and can be used for peripheral nerve protection and myelination. Microcapsule technology largely mitigates immune rejection of transplanted ...Schwann cell transplantation is a promising method to promote neural repair, and can be used for peripheral nerve protection and myelination. Microcapsule technology largely mitigates immune rejection of transplanted cells. We previously showed that microencapsulated olfactory ensheathing cells can reduce neuropathic pain and we hypothesized that microencapsulated Schwann cells can also inhibit neuropathic pain. Rat Schwann cells were cultured by subculture and then microencapsulated and were tested using a rat chronic constriction injury（CCI） neuropathic pain model. CCI rats were treated with Schwann cells or microencapsulated Schwann cells and were compared with sham and CCI groups. Mechanical withdrawal threshold and thermal withdrawal latency were assessed preoperatively and at 1, 3, 5, 7, 9, 11 and 14 days postoperatively. The expression of P2X3 receptors in L4-5 dorsal root ganglia of the different groups was detected by double-label immunofluorescence on day 14 after surgery. Compared with the chronic constriction injury group, mechanical withdrawal threshold and thermal withdrawal latency were higher, but the expression of P2X3 receptors was remarkably decreased in rats treated with Schwann cells and microencapsulated Schwann cells, especially in the rats transplanted with microencapsulated Schwann cells. The above data show that microencapsulated Schwann cell transplantation inhibits P2X3 receptor expression in L4-5 dorsal root ganglia and neuropathic pain.展开更多
Background:Pulsed radiofrequency(PRF)is a minimally invasive interventional technique that provides a novel and effective treatment strategy for neuropathic pain(NP).PRF is advantageous because it does not damage nerv...Background:Pulsed radiofrequency(PRF)is a minimally invasive interventional technique that provides a novel and effective treatment strategy for neuropathic pain(NP).PRF is advantageous because it does not damage nerves and avoids sensory loss after treatment.At present,animal studies have demonstrated that PRF is safe and effective for relieving the NP associated with sciatic nerve damage in rats with chronic constriction injury(CCI).However,the mechanism through which this effect occurs is unknown.An increasing body of evidence shows that the expression of the P2X ligand-gated ion channel 3(P2X3)receptor is closely related to NP;this study was to investigate whether the expression of this receptor is involved in NP relief due to PRF.Methods:A total of 36 healthy adult male Sprague-Dawley(SD)rats were randomly divided into three groups:Sham group,CCI group,and PRF group.The right sciatic nerve was ligated in CCI group and PRF group to establish a CCI model;the right sciatic nerve was separated but not ligated in Sham group.On day 14 after the operation,PRF was administered to the ligated sciatic nerve in PRF group(42℃,45 V,2 min).A non-live electrode was placed at the exposed sciatic nerve for the rats in Sham and CCI groups.The hindpaw withdrawal threshold(HWT)and thermal withdrawal latency(TWL)were measured at the right hindpaw at different time points before and after PRF or sham therapy.On day 28 after treatment,the dorsal root ganglion(DRG)and spinal dorsal horn of the right L4-6 were harvested from each group to determine the mRNA and protein levels of the P2X3 receptor.Results:On day 28 after PRF treatment,the HWT(8.33±0.67 g vs.3.62±0.48 g)and TWL(25.42±1.90 s vs.15.10±1.71 s)were significantly higher in PRF group as compared to CCI group(P<0.05).The mRNA expression of the P2X3 receptor in the DRG in PRF group was 23.7%lower than that in CCI group(P<0.05),in the spinal dorsal horns in PRF group was 22.7%lower than that in CCI group(P<0.05).The protein expression of the P2X3 receptor in the DRG in PRF group was 27.8%lower than that in CCI group(P<0.05),in the spinal dorsal horns in PRF group was 35.6%lower than that in CCI group(P<0.05).Conclusion:PRF possibly reduces NP in CCI rats by inhibiting the expression of the P2X3 receptor in the L4-6 DRG and spinal dorsal horns.展开更多
The P2X3 receptor plays a vital role in sensory processing and transmission. The assembly and trafficking of the P2X3 receptor are important for its function in primary sensory neurons. As an important inflammation me...The P2X3 receptor plays a vital role in sensory processing and transmission. The assembly and trafficking of the P2X3 receptor are important for its function in primary sensory neurons. As an important inflammation mediator, ATP is released from different cell types around primary sensory neurons, especially under pathological pain conditions. Here, we showthat α, β-MeATP dramatically promoted membrane delivery of the P2X3 receptor both in HEK293T celts expressing recombinant P2X3 receptor and in rat primary sensory neurons. α, β-MeATP induced P2X3 receptor-mediated Ca^2＋ influx, which further activated Ca^2＋/calmodulin-dependent protein kinase Ilec （CaMKIIα）. The N terminus of the P2X3 receptor was responsible for CaMKIleα binding, whereas Thr38s in the C terminus was phosphorylated by CaMKIIα. Thr^388 phosphorylation increased P2X3 receptor binding to caveoUn-1. CaveoUn-1 knockdown abrogated the α, β-MeATP-induced membrane insertion of the P2X3 receptor. Moreover,α, β-MeATP drove the CaMKIlec-mediated membrane coinsertion of the P2X2 receptor with the P2X3 receptor. The increased P2X3 receptors on the cell membrane that are due to Thr388 phosphorytation facilitated P2X3 receptor-mediated signal transduction. Together, our data indicate that CaMKIIoL and caveoUn-1 cooperate to drive Ugand-induced membrane delivery of the P2X3 receptor and may provide a mechanism of P2X3 receptor sensitization in pain development.展开更多
Objective:To investigate the role of serotonin reuptake transporter(SERT)and P2X3 receptor of dorsal root ganglion(DRG)in regulating visceral hypersensitivity of rats with irritable bowel syndrome(IBS)by electroacupun...Objective:To investigate the role of serotonin reuptake transporter(SERT)and P2X3 receptor of dorsal root ganglion(DRG)in regulating visceral hypersensitivity of rats with irritable bowel syndrome(IBS)by electroacupuncture(EA).Methods:Male Sprague-Dawley and SERT^(-/-)rats were subjected to preparing IBS visceral hypersensitivity models with 2,4,6-trinitrobenzene sulfonic acid(TNBS)enema.Three weeks post-modeling,interventions including EA,intrathecal injection,and EA plus intrathecal injection were applied,respectively.Hematoxylin-eosin staining and abdominal withdrawal reflex(AWR)score were used to confirm the successful establishment of the IBS model.AWR score,whole-cell patch clamp technique,and Western blotting assay were used to evaluate the changes in visceral pain sensitivity,electrophysiological properties of DRG neurons,and the expression of DRG P2X3 receptor and SERT in IBS rats.Results:Compared to the model group,the AWR score in the EA group decreased significantly(P<0.05),the resting membrane potential(P<0.05)and the number of action potentials(P<0.05)of DRG neurons reduced,and the baseline intensity increased(P<0.05);additionally,the expression of P2X3 receptor in DRG decreased(P<0.01),and the SERT expression increased(P<0.05).Compared to the P2X3 receptor agonist group,the SERT protein expression in DRG was higher in the EA group.In SERT^(-/-)rats,the P2X3 receptor expression in DRG increased in the EA group compared to the model group(P<0.01).Conclusion:EA modulates the electrophysiological characteristics of intestinal primary sensory neurons by regulating the expression of SERT and P2X3 receptor in DRG of IBS rats.This modulation may contribute to the mechanism by which EA alleviates peripheral sensitization of visceral pain in IBS rats.展开更多
Objective To observe the therapeutic effect of mild moxibustion on irritable bowel syndrome(IBS)visceral hyperalgesia model rats and its regulatory effect on P2X3 receptors in the spinal cord,anterior cingutate cortex...Objective To observe the therapeutic effect of mild moxibustion on irritable bowel syndrome(IBS)visceral hyperalgesia model rats and its regulatory effect on P2X3 receptors in the spinal cord,anterior cingutate cortex(ACC)and thalamic ventral posterolateral nucleus(VPL).Methods Thirty 8-day-old newborn rats were randomly divided into a normal group(n=6)and a modeling group(n=24)according to the completely random number table method.Rats in the normal group were bred routinely,and those in the modeling group were subjected to preparing IBS chronic visceral hyperalgesia model using colorectal distention(CRD)in stimulation method.Rats successfully modelled were re-divided into a model group,a mild moxibustion group,a P2X3 receptor antagonist group,and a normal saline group according to the completely random number table method with 6 rats in each group.Rats in each group received corresponding interventions from the 37-day old,once a day for 7 consecutive days.Immunohistochemistry and Western blot assays were used to detect P2X3 protein expressions in the spinal cord,ACC and VPL of rats.Results Under different intensities of CRD stimulation,the abdominal withdrawal reflex(AWR)scores of the model group were significantly increased versus the normal group(all P<0.05);the AWR scores of the mild moxibustion group and the P2X3 receptor antagonist group were significantly reduced versus the model group(all P<0.01).The P2X3 protein expressions in rat spinal cord,ACC and VPL tissues of the model group were significantly increased versus the normal group(all P<0.01);the P2X3 protein expressions in rat spinal cord,ACC and VPL tissues of the mild moxibustion group and the P2X3 receptor antagonist group were significantly reduced versus the model group(all P<0.01).Conclusion Mild moxibustion can inhibit the P2X3 receptor expressions in the spinal cord,ACC,and VPL tissues of IBS visceral hyperalgesia model rats,which may be the mechanism of mild moxibustion in relieving the central sensitization of rats with IBS visceral hyperalgesia.展开更多
基金supported by the National Natural Science Foundation of China,No.81760418 and 81260190the Natural Science Foundation of Jiangxi Province,No.20132BAB205023,20151BAB205022+1 种基金a grant from Science and Technology Research Project of Jiangxi Education Department,No.GJJ13159a grant from the Science and Technology Program of Department of Health of Jiangxi Province,No.20173010
文摘Schwann cell transplantation is a promising method to promote neural repair, and can be used for peripheral nerve protection and myelination. Microcapsule technology largely mitigates immune rejection of transplanted cells. We previously showed that microencapsulated olfactory ensheathing cells can reduce neuropathic pain and we hypothesized that microencapsulated Schwann cells can also inhibit neuropathic pain. Rat Schwann cells were cultured by subculture and then microencapsulated and were tested using a rat chronic constriction injury（CCI） neuropathic pain model. CCI rats were treated with Schwann cells or microencapsulated Schwann cells and were compared with sham and CCI groups. Mechanical withdrawal threshold and thermal withdrawal latency were assessed preoperatively and at 1, 3, 5, 7, 9, 11 and 14 days postoperatively. The expression of P2X3 receptors in L4-5 dorsal root ganglia of the different groups was detected by double-label immunofluorescence on day 14 after surgery. Compared with the chronic constriction injury group, mechanical withdrawal threshold and thermal withdrawal latency were higher, but the expression of P2X3 receptors was remarkably decreased in rats treated with Schwann cells and microencapsulated Schwann cells, especially in the rats transplanted with microencapsulated Schwann cells. The above data show that microencapsulated Schwann cell transplantation inhibits P2X3 receptor expression in L4-5 dorsal root ganglia and neuropathic pain.
基金supported by grants from Foundation for The Excellent Medical Staff of Beijing(No.2011-3-034 and No.2014-3-035).
文摘Background:Pulsed radiofrequency(PRF)is a minimally invasive interventional technique that provides a novel and effective treatment strategy for neuropathic pain(NP).PRF is advantageous because it does not damage nerves and avoids sensory loss after treatment.At present,animal studies have demonstrated that PRF is safe and effective for relieving the NP associated with sciatic nerve damage in rats with chronic constriction injury(CCI).However,the mechanism through which this effect occurs is unknown.An increasing body of evidence shows that the expression of the P2X ligand-gated ion channel 3(P2X3)receptor is closely related to NP;this study was to investigate whether the expression of this receptor is involved in NP relief due to PRF.Methods:A total of 36 healthy adult male Sprague-Dawley(SD)rats were randomly divided into three groups:Sham group,CCI group,and PRF group.The right sciatic nerve was ligated in CCI group and PRF group to establish a CCI model;the right sciatic nerve was separated but not ligated in Sham group.On day 14 after the operation,PRF was administered to the ligated sciatic nerve in PRF group(42℃,45 V,2 min).A non-live electrode was placed at the exposed sciatic nerve for the rats in Sham and CCI groups.The hindpaw withdrawal threshold(HWT)and thermal withdrawal latency(TWL)were measured at the right hindpaw at different time points before and after PRF or sham therapy.On day 28 after treatment,the dorsal root ganglion(DRG)and spinal dorsal horn of the right L4-6 were harvested from each group to determine the mRNA and protein levels of the P2X3 receptor.Results:On day 28 after PRF treatment,the HWT(8.33±0.67 g vs.3.62±0.48 g)and TWL(25.42±1.90 s vs.15.10±1.71 s)were significantly higher in PRF group as compared to CCI group(P<0.05).The mRNA expression of the P2X3 receptor in the DRG in PRF group was 23.7%lower than that in CCI group(P<0.05),in the spinal dorsal horns in PRF group was 22.7%lower than that in CCI group(P<0.05).The protein expression of the P2X3 receptor in the DRG in PRF group was 27.8%lower than that in CCI group(P<0.05),in the spinal dorsal horns in PRF group was 35.6%lower than that in CCI group(P<0.05).Conclusion:PRF possibly reduces NP in CCI rats by inhibiting the expression of the P2X3 receptor in the L4-6 DRG and spinal dorsal horns.
文摘The P2X3 receptor plays a vital role in sensory processing and transmission. The assembly and trafficking of the P2X3 receptor are important for its function in primary sensory neurons. As an important inflammation mediator, ATP is released from different cell types around primary sensory neurons, especially under pathological pain conditions. Here, we showthat α, β-MeATP dramatically promoted membrane delivery of the P2X3 receptor both in HEK293T celts expressing recombinant P2X3 receptor and in rat primary sensory neurons. α, β-MeATP induced P2X3 receptor-mediated Ca^2＋ influx, which further activated Ca^2＋/calmodulin-dependent protein kinase Ilec （CaMKIIα）. The N terminus of the P2X3 receptor was responsible for CaMKIleα binding, whereas Thr38s in the C terminus was phosphorylated by CaMKIIα. Thr^388 phosphorylation increased P2X3 receptor binding to caveoUn-1. CaveoUn-1 knockdown abrogated the α, β-MeATP-induced membrane insertion of the P2X3 receptor. Moreover,α, β-MeATP drove the CaMKIlec-mediated membrane coinsertion of the P2X2 receptor with the P2X3 receptor. The increased P2X3 receptors on the cell membrane that are due to Thr388 phosphorytation facilitated P2X3 receptor-mediated signal transduction. Together, our data indicate that CaMKIIoL and caveoUn-1 cooperate to drive Ugand-induced membrane delivery of the P2X3 receptor and may provide a mechanism of P2X3 receptor sensitization in pain development.
文摘Objective:To investigate the role of serotonin reuptake transporter(SERT)and P2X3 receptor of dorsal root ganglion(DRG)in regulating visceral hypersensitivity of rats with irritable bowel syndrome(IBS)by electroacupuncture(EA).Methods:Male Sprague-Dawley and SERT^(-/-)rats were subjected to preparing IBS visceral hypersensitivity models with 2,4,6-trinitrobenzene sulfonic acid(TNBS)enema.Three weeks post-modeling,interventions including EA,intrathecal injection,and EA plus intrathecal injection were applied,respectively.Hematoxylin-eosin staining and abdominal withdrawal reflex(AWR)score were used to confirm the successful establishment of the IBS model.AWR score,whole-cell patch clamp technique,and Western blotting assay were used to evaluate the changes in visceral pain sensitivity,electrophysiological properties of DRG neurons,and the expression of DRG P2X3 receptor and SERT in IBS rats.Results:Compared to the model group,the AWR score in the EA group decreased significantly(P<0.05),the resting membrane potential(P<0.05)and the number of action potentials(P<0.05)of DRG neurons reduced,and the baseline intensity increased(P<0.05);additionally,the expression of P2X3 receptor in DRG decreased(P<0.01),and the SERT expression increased(P<0.05).Compared to the P2X3 receptor agonist group,the SERT protein expression in DRG was higher in the EA group.In SERT^(-/-)rats,the P2X3 receptor expression in DRG increased in the EA group compared to the model group(P<0.01).Conclusion:EA modulates the electrophysiological characteristics of intestinal primary sensory neurons by regulating the expression of SERT and P2X3 receptor in DRG of IBS rats.This modulation may contribute to the mechanism by which EA alleviates peripheral sensitization of visceral pain in IBS rats.
文摘Objective To observe the therapeutic effect of mild moxibustion on irritable bowel syndrome(IBS)visceral hyperalgesia model rats and its regulatory effect on P2X3 receptors in the spinal cord,anterior cingutate cortex(ACC)and thalamic ventral posterolateral nucleus(VPL).Methods Thirty 8-day-old newborn rats were randomly divided into a normal group(n=6)and a modeling group(n=24)according to the completely random number table method.Rats in the normal group were bred routinely,and those in the modeling group were subjected to preparing IBS chronic visceral hyperalgesia model using colorectal distention(CRD)in stimulation method.Rats successfully modelled were re-divided into a model group,a mild moxibustion group,a P2X3 receptor antagonist group,and a normal saline group according to the completely random number table method with 6 rats in each group.Rats in each group received corresponding interventions from the 37-day old,once a day for 7 consecutive days.Immunohistochemistry and Western blot assays were used to detect P2X3 protein expressions in the spinal cord,ACC and VPL of rats.Results Under different intensities of CRD stimulation,the abdominal withdrawal reflex(AWR)scores of the model group were significantly increased versus the normal group(all P<0.05);the AWR scores of the mild moxibustion group and the P2X3 receptor antagonist group were significantly reduced versus the model group(all P<0.01).The P2X3 protein expressions in rat spinal cord,ACC and VPL tissues of the model group were significantly increased versus the normal group(all P<0.01);the P2X3 protein expressions in rat spinal cord,ACC and VPL tissues of the mild moxibustion group and the P2X3 receptor antagonist group were significantly reduced versus the model group(all P<0.01).Conclusion Mild moxibustion can inhibit the P2X3 receptor expressions in the spinal cord,ACC,and VPL tissues of IBS visceral hyperalgesia model rats,which may be the mechanism of mild moxibustion in relieving the central sensitization of rats with IBS visceral hyperalgesia.
