Effects of iodoacetic acid drinking water disinfection byproduct on the gut microbiota and its metabolism in rats.

Iodoacetic acid (IAA) is an unregulated disinfection byproduct in drinking water and has been shown to exert cytotoxicity, genotoxicity, tumorigenicity, and reproductive and developmental toxicity. However, the effects of IAA on gut microbiota and its metabolism are still unknown, especially the association between gut microbiota and the metabolism and toxicity of IAA. In this study, female and male Sprague-Dawley rats were exposed to IAA at 0 and 16 mg/kg bw/day daily for 8 weeks by oral gavage. Results of 16S rRNA gene sequencing showed that IAA could alter the diversity, relative abundance and function of gut microbiota in female and male rats. IAA also increased the abundance of genes related to steroid hormone biosynthesis in the gut microbiota of male rats. Moreover, metabolomics profiling revealed that IAA could significantly disturb 6 and 13 metabolites in the feces of female and male rats, respectively. In female rats, the level of androstanediol increased in the IAA treatment group. These results were consistent with our previous findings, where IAA was identified as an androgen disruptor. Additionally, the perturbed gut microbiota and altered metabolites were correlated with each other. The results of this study indicated that IAA could disturb gut microbiota and its metabolism. These changes in gut microbiota and its metabolism were associated with the reproductive and developmental toxicity of IAA.

Androgenic and Teratogenic Effects of Iodoacetic Acid Drinking Water Disinfection Byproduct in Vitro and in Vivo.

Iodoacetic acid (IAA) is the most genotoxic iodinated disinfection byproduct known in drinking water. Previous studies have shown that IAA may be an endocrine disruptor. However, whether IAA has reproductive and developmental toxicity remains unclear. In this study, the reproductive and developmental toxicity of IAA was evaluated using a battery of in vitro and in vivo reproductive/developmental toxicity screening tests. The results of E-Screen, uterotrophic, and H295R steroidogenesis assays were negative. The Hershberger bioassay revealed that IAA could induce significant increases in absolute and relative weights of paired Cowper's glands. Moreover, there was an increasing trend in the relative weights of the ventral prostate. The micromass test showed that IAA could inhibit the differentiation of midbrain and limb bud cells. A reproductive/developmental toxicity screening test showed that IAA resulted in significantly increased relative weights of testis and seminal vesicles plus coagulating glands in parental male rats, with a dose-response relationship. IAA could not only induce head congestion in offspring but also decrease litter weight, viability index, and anogenital distance index of male pups on postnatal day 4. All these results indicated that IAA had reproductive and developmental toxicity.

Occurrence and toxicity of halobenzoquinones as drinking water disinfection byproducts.

Halobenzoquinones (HBQs) are emerging unregulated drinking water disinfection byproducts (DBPs) that are more toxic than regulated DBPs. This study aimed to determine the distribution and formation of HBQs in drinking water from water treatment plants in China, compare their chronic cytotoxicity and their induction of chromosomal damage in Chinese hamster ovary cells, and analyze the correlation of HBQ toxicity with their physicochemical parameters. Two HBQs, 2,6-dichloro-1,4-benzoquinone (2,6-DCBQ) and 2,6-dibromo-1,4-benzoquinone (2,6-DBBQ), were detected in finished water and tap water in China. The concentrations were in the ranges of <2.6-19.70 ng/L for 2,6-DCBQ and <0.38-1.8 ng/L for 2,6-DBBQ. Chemical oxygen demand and residual chlorine were positively correlated with HBQ formation. The HBQ concentration was lower in a drinking water treatment plant using chlorine dioxide. High Ca2+ in tap water decreased the HBQ level. The rank order of HBQ by cytotoxicity was 2-chloro-1,4-benzoquinone > 2,3-diiodo-1,4-benzoquinone > 2,6-diiodo-1,4-benzoquinone > 2,6-dibromo-1,4-benzoquinone > 2,5-dibromo-1,4-benzoquinone > 2,5-dichloro-1,4-benzoquinone > 2,6-dichloro-1,4-benzoquinone > tetrachloro-1,4-benzoquinone > 2,3,6-trichloro-1,4-benzoquinone, and for their genotoxicity, 2,5-dichloro-1,4-benzoquinone > 2,6-dichloro-1,4-benzoquinone > 2,3-diiodo-1,4-benzoquinone > 2,6-diiodo-1,4-benzoquinone > tetrachloro-1,4-benzoquinone > 2,5-dibromo-1,4-benzoquinone > 2,6-dibromo-1,4-benzoquinone > 2,3,6-trichloro-1,4-benzoquinone. The cytotoxicity of six dihalo-HBQs was negatively correlated with the octanol-water partition coefficient (r = -0.971, P < 0.05), molar refractivity (r = -0.956, P < 0.05), energy of the highest occupied molecular orbital (EHOMO) (r = -0.943, P < 0.05), and polar surface area (r = -0.829, P < 0.05). The genotoxicity of these three pairs of dihalo-HBQ isomers followed the same order as their EHOMO values. This study reveals the occurrence and formation of HBQs in drinking water in China and systematically evaluates the chromosomal damage caused by nine HBQs in mammalian cells.

Occurrence and formation of halobenzoquinones in indoor and outdoor swimming pool waters of Nanning City, Southwest China.

Disinfection byproducts (DBPs) in swimming pool have elicited increasing worldwide concern due to their potential health risks. However, only trihalomethanes (THMs) are regulated by several local governing bodies. Studies indicated that specific unregulated DBP classes would drive disinfected water toxicity in addition to THMs. Halobenzoquinones (HBQs), a type of emerging unregulated DBPs, have been shown to be possible bladder cancer carcinogens. This study aimed to determine the distribution and formation of HBQs in indoor and outdoor swimming pool waters of Nanning City, Southwest China. Seven HBQs in water from seven public indoor and outdoor swimming pools were examined using an effective ultra-performance liquid chromatography-tandem mass spectrometry method. Results suggest the presence of 2,6-dichloro-1,4-benzoquinone in all the swimming pool waters in the range of 4.56-45.30 ng/L. Furthermore, 2,6-dibromo-1,4-benzoquinone and 3,4,5,6-tetrachloro-1,2-benzoquinone (TetraC-1,2-BQ) were detected in two pools at concentrations of < 0.38-14.20 and < 0.54-2.60 ng/L, respectively. The swimming pool water featured higher HBQs than input tap water, and TetraC-1,2-BQ was only detected in pool water. Higher HBQ levels were observed in the indoor pools than in the outdoor pools. These findings demonstrate that low NH3-N, high chloride, humic acid, chemical oxygen demand, and UV254 in the indoor pools increased the HBQ formation. This study is the first to reveal the occurrence and formation of HBQs in water from Chinese indoor and outdoor swimming pools. The findings should be useful in the management of these governing factors and HBQ controls in swimming pools.

Folic acid contributes to peripheral nerve injury repair by promoting Schwann cell proliferation, migration, and secretion of nerve growth factor.

After peripheral nerve injury, intraperitoneal injection of folic acid improves axon quantity, increases axon density and improves electromyography results. However, the mechanisms for this remain unclear. This study explored whether folic acid promotes peripheral nerve injury repair by affecting Schwann cell function. Primary Schwann cells were obtained from rats by in vitro separation and culture. Cell proliferation, assayed using the Cell Counting Kit-8 assay, was higher in cells cultured for 72 hours with 100 mg/L folic acid compared with the control group. Cell proliferation was also higher in the 50, 100, 150, and 200 mg/L folic acid groups compared with the control group after culture for 96 hours. Proliferation was markedly higher in the 100 mg/L folic acid group compared with the 50 mg/L folic acid group and the 40 ng/L nerve growth factor group. In Transwell assays, the number of migrated Schwann cells dramatically increased after culture with 100 and 150 mg/L folic acid compared with the control group. In nerve growth factor enzyme-linked immunosorbent assays, treatment of Schwann cell cultures with 50, 100, and 150 mg/L folic acid increased levels of nerve growth factor in the culture medium compared with the control group at 3 days. The nerve growth factor concentration of Schwann cell cultures treated with 100 mg/L folic acid group was remarkably higher than that in the 50 and 150 mg/L folic acid groups at 3 days. Nerve growth factor concentration in the 10, 50, and 100 mg/L folic acid groups was higher than that in the control group at 7 days. The nerve growth factor concentration in the 50 mg/L folic acid group was remarkably higher than that in the 10 and 100 mg/L folic acid groups at 7 days. In vivo, 80 µg/kg folic acid was intraperitoneally administrated for 7 consecutive days after sciatic nerve injury. Immunohistochemical staining showed that the number of Schwann cells in the folic acid group was greater than that in the control group. We suggest that folic acid may play a role in improving the repair of peripheral nerve injury by promoting the proliferation and migration of Schwann cells and the secretion of nerve growth factors.

Clinical analysis of open surgical drainage approach in treating severe acute pancreatitis with walled-off pancreatic necrosis / 中华胰腺病杂志

Objective To investigate the effect of open surgical drainage approach for the treatment of walled-off pancreatic necrosis ( WOPN) in severe acute pancreatitis. Methods Clinical data of 154 WOPN patients admitted in the First Affiliated Hospital of Xinjiang Medical University from January 2005 to October 2016 were retrospectively analyzed. Traditional open debridement necrosectomy was performed in 83 patients from January 2005 to October 2012 ( debridement group) , and small abdominal incision with low-position open surgical drainage was performed in 71 patients from October 2012 to October 2016 ( drainage group ) . The clinical outcomes of two groups were analyzed and compared. Results 43 cases (51. 8％) in debridement group had postoperative intraperitoneal reinfection, while there were only 13 cases with postoperative intraperitoneal reinfection (18. 3％) in drainage group;18 cases (21. 7％) in debridement group had surgery-related digestive tract fistula, while there were only 4 cases with surgery-related digestive tract fistula (5. 6％) in drainage group; the differences were statistically significant (χ2 = 18. 55, P=0. 001; χ2 = 11. 35, P=0. 002). 15 patients (18. 1％) in debridement group and only 2 patients (2. 8％) in drainage group died. The mortality in drainage group were obviously lower than that in debridement group, and the difference was statistically significant (χ2 = 9. 07, P<0. 05 ). 62 cases ( 74. 7％) in debridement group and 55 cases (77. 5％) in drainage group were cured directly, respectively. No significant difference was found between two groups. However, 3 cases (3. 6％) in debridement group and 12 cases (16. 9％) in drainage group were cured by the way of small intestinal fistula in the late stage of intubation, and the latter was higher than the former with statistically significant(χ2 =5. 989,P=0. 014). Conclusions Compared with open debridement necrosectomy, the abdominal infection rate, digestive tract fistula rate and mortality of open surgical drainage were all significantly reduced , which may be a better treatment for WOPN.

Iodoacetic Acid Disrupting the Thyroid Endocrine System in Vitro and in Vivo.

Exposure to drinking water disinfection byproducts (DBPs) is potentially associated with adverse developmental effects. Iodoacetic acid (IAA), an unregulated DBP, has been shown to be cytotoxic, mutagenic, genotoxic, and tumorigenic. However, its endocrine-disrupting effects remain unknown. This study evaluated the IAA-induced disruption of the thyroid endocrine system using in vitro and in vivo assays. Rat pituitary tumor GH3 cells were treated with IAA in the presence and absence of triiodothyronine (T3). IAA exposure significantly reduced T3-activated GH3 cell proliferation, indicating the antagonistic activity of IAA in vitro. Sprague-Dawley rats were also subjected to IAA treatment through oral gavage for 28 consecutive days. IAA exposure significantly down-regulated the mRNA expression levels of the thyrotropin receptor (TSHR), the sodium/iodide symporter (NIS), and type I deiodinase and simultaneously reduced the protein expression levels of TSHR and NIS. IAA exposure decreased T3 levels but increased the weights of hypothalamus and the levels of thyrotropin releasing hormone and thyrotropin. In addition, IAA induced the formation of smaller and more depleted follicles or even vacuolization in the thyroid. These results suggested that IAA potentially disrupts the thyroid endocrine system both in vitro and in vivo.

Methylation status of CDH1 gene in invasive ductal carcinoma of breast and its clinical significance / 重庆医学

Objective To explore the significance of gene promoter methylation of CDH1 in breast invasive ductal carcinoma.Methods The gene promoter methylation of CDH1 and E-cadherin expression status in breast cancer tissues,adjacent tissues and normal breast tissues were detected by using methylation specific polymerase chain reaction (PCR) and immunohistochemistry (SP) method.The clinicopathological data (genetic background,age,tumor size,axillary lymph node metastasis,tumor cells grading,clinical staging and molecular subtype) were collected,and analysed the clinical significance of gene promoter methylation of CDH1 in breast cancer.Results Among the 250 patients with breast cancer,113 cases were found gene promoter methylation of CDH1,and the methylation rate was 45.20％.Compared with patients with unmethylated CDH1 gene promoter,the E-cadherin protein expression was reduced in patients with methylated CDH1 gene promoter,there was statistically significant difference (x2 =21.360,P＜0.01).The univariate analysis showed that statistically significant differences were found in axillary lymph node metastasis (x2=19.086,P＜0.01),histological grading of tumor (x2 =8.487,P=0.014),CerbB-2 expression (x2=9.475,P=0.002) and molecular typing (x2 =25.482,P＜0.01) between patients with methylated and unmethylated CDH1 gene promoter.The COX regression analysis showed that there was significant difference in 5-year survival rate between patients with methylated and unmethylated CDH1 gene promoter(P＜0.01).Conclusion Methylation of CDH1 gene promoter causes decreasedexpression of mRNA,and is associated with axillary lymph node metastasis in breast cancer,which suggests that methylation of CDH1 gene promoter plays a certain role in breast cancer progression.

Analysis of pathological features and prognosis of T1 invasive ductal breast carcinoma with calcification / 重庆医学

Objective To explore the pathological characteristics and prognostic influencing factors of T1 invasive ductal breast carcinoma with calcification.Methods The clinicopathological and follow-up data in 172 patients with initially treated operable T1 invasive ductal breast cancer in this hospital from June 2012 to June 2013 were analyzed restrospectively.The patients were divided into the calcification group and non-calcification group based on the breast X-ray image features.The differences of pathological characteristics between two groups,related factors,and relationship between the calcification expression with patient survival were analyzed.Results The pathological types,lymph node metastasis,Her-2 overexpression,TNM stage and Ki-67 had statistically significant difference between the calcification group and non-calcification group(P＜0.05).The multivariate analysis showed that the cases type,lymph node metastasis and Ki-67 were the related risk factors affecting the calcification expression(P＜0.05).The 3-year disease-free survival rate in the the calcifi cation group and non-calcification group were 87.30％ and 95.06％ respectively.The lymph node status and calcification were the independent predictive risk factors affecting the disease-free survival time of invasive ductal breast carcinoma(P＜0.05).Conclusion Calcification is visible X-ray risk factor of T1 invasive ductal breast carcinoma prognosis.

Clinical effect of non-invasive positive pressure ventilation for treatment of acute left heart failure af-ter mitral valve replacement / 新乡医学院学报

Objective To explore the clinical effect of non-invasive positive pressure ventilation(NPPV)for treatment of acute left heart failure after mitral valve replacement. Methods Sixty patients with acute left heart failure after mitral valve replacement in Xinxiang Central Hospital from April 2009 to August 2017 were selected. The patients were divided into control group and NPPV group,with 30 patients in each group. The patients in the control group were treated with double oxygen ab-sorption (mask and nasal catheter),strong heart,diuresis and dilated blood vessels. Based on the treatment of control group, the patients in NPPV group were treated with NPPV therapy. The plasma N-terminal pro-B-type natriuretic peptide(NT-proB-NP)level of patients in the two groups was monitored by rapid determination of immunofluorescence before treatment and 6,24 hours after treatment. The respiratory frequency,blood oxygen saturation,heart rate and oxygen partial pressure monitoring of patients in the two groups was monitored before treatment and 2,6 and 24 hours after treatment. Results The total effective rate of patients in the control group and NPPV group was 92. 4％(26 / 28)and 96. 6％(28 / 29)respectively;there was no sig-nificant difference in the total effective rate between the two groups(χ2 = 1. 25,P > 0. 05). There was no significant difference in the plasma NT-proBNP level between the two groups before treatment (P > 0. 05);the level of NT-proBNP at 6,24 h after treatment was significantly lower than that before treatment in the two groups (P < 0. 05);the level of NT-proBNP of patients in the NPPV group was significantly lower than that in the control group at 6,24 h after treatment (P < 0. 05). There was no significant difference in the respiratory frequency,blood oxygen saturation,heart rate and oxygen partial pressure between the two groups before treatment(P > 0. 05). Compared with before treatment,the respiratory frequency and heart rate of patients were decreased and the blood oxygen saturation,oxygen partial pressure were increased at 2,6,24 h after treatment in the two groups (P < 0. 05). There was no significant difference in the oxygen partial pressure between the two groups at 2 h after treat-ment(P > 0. 05);the oxygen partial pressure of patients in the NPPV group was significantly higher than that in the control group at 6,24 h after treatment(P < 0. 05);there was no significant difference in the respiratory frequency,blood oxygen satu-ration and heart rate between the two groups at each time piont after treatment(P > 0. 05). Conclusion NPPV is an effective treatment for acute left heart failure after mitral valve replacement.

Application of CRISPR/Cas 9 system for the research of retinal development and inherited retinal diseases / 眼科新进展

The system of clustered regularly interspaced short palindromic repeats (CRISPR) and CRISPR-associated nuclease (Cas) 9 is an effective tool for revising the genome with great accuracy,and boost the advances in life science.By employing this system,we discover the regulation role of key gene during retina development and correct the abnormal mutation of these genes.In this paper,we summarize CRISPR-based technologies that enable mammalian genome editing and their various applications.And CRISPR/Cas9 may be a promising tool to disclosure the mechanism of retinal diseases so as to develop novel treatment for patients with retinitis pigmentosa.

Application of CRISPR/Cas 9 system for the research of retinal development and inherited retinal diseases / 眼科新进展

The system of clustered regularly interspaced short palindromic repeats (CRISPR) and CRISPR-associated nuclease (Cas) 9 is an effective tool for revising the genome with great accuracy,and boost the advances in life science.By employing this system,we discover the regulation role of key gene during retina development and correct the abnormal mutation of these genes.In this paper,we summarize CRISPR-based technologies that enable mammalian genome editing and their various applications.And CRISPR/Cas9 may be a promising tool to disclosure the mechanism of retinal diseases so as to develop novel treatment for patients with retinitis pigmentosa.

Involvement of RNA helicase p68 in skin wound healing process in rats / 中华创伤杂志(英文版)

<p><b>PURPOSE</b>RNA helicase p68 plays an important role in organ development and maturation through tuning cell proliferation. However, the character and role of p68 in the whole wound healing process need more study.</p><p><b>METHODS</b>First, we characterize expression of p68 in normal rat skin development postnatal. Then, we assayed dynamic change of p68 in rat skin from different stage after injury, and explored the role of p68 in proliferation and migration of three types of wound healing related cells.</p><p><b>RESULTS</b>p68 was down-regulated during skin developmental and maturation process, up-regulated after wound, peaked on day 14 and then significantly decreased. Wound fluid enhanced wound healing related cell proliferation and up-regulated expression of p68. Conversely, reducing p68 expression by RNA interference resulted in significantly slower proliferation and migration.</p><p><b>CONCLUSION</b>Our results define an important role of RNA helicase p68 in skin wound healing process.</p>

Association between single nucleotide polymorphisms of ER β gene and susceptibility of breast cancer in Xinjiang Uygur / 肿瘤研究与临床

Obiective To investigate the association between single nucleotide polymorphisms (SNPs) of ER β gene and susceptibility of breast cancer in Uygur women in Xinjiang.Methods A case-control study was designed to explore the genotypes of Rsa Ⅰ (G/A) of ER β gene,detected by PCR-restriction fragment length polymorphism (PCR-RFLP) assay,in 112 breast cancer cases of Uygur women and 139 medical health cases of Uygur women.The association between SNPs of ER β gene and risk of breast cancer in Uygur women was analyzed by unconditional Logistic regression model.Results The frequencies of genotypes of Rsa Ⅰ (G/A) of ER β gene in cancer group and control group were 83.0 ％ and 17.0 ％,73.4 ％ and 26.6 ％,respectively.Rsa Ⅰ (G/A) locus allele frequency were 91.5 ％ and 8.5 ％,86.7 ％ and 13.3 ％,respectively.There were no statistically differences between the cancer cases and control cases (x2 =3.335,P =0.068.x2 =2.917,P =0.088).Presence of estrogen exposure history of two groups for genotypes distribution were 74.2 ％ and 25.8 ％,86.4 ％ and 13.6 ％,respectively.Any family history of cancer in the two groups for the genotypes distribution were 100 ％ and 0,72.8 ％ and 27.2 ％ respectively.There were statistically significant difference between two groups (P =0.046,P =0.001).Compared with wild-type genotype GG,the GA type with estrogen exposure and without a family history of cancer showed a lower incidence of breast cancer in Uygur women (OR =0.385,95 ％ CI 0.148-0.999.OR =0.285,95 ％ CI 0.134-0.605).Conclusions ER β gene SNP is associated with breast cancer of estrogen exposure and no family history of cancer factors.GA genotype may be a protective factor for Uygur women with breast cancer.

Isolation and identification of two new diterpenoid from Rubus corchorifolius L. f / 药学学报

To study the constituents of Rubus corchorifolius L. f, the constituents were separated by using various chromatographies and the structures were identified on the basis of chemical and spectral analysis. Two compounds were isolated from Rubus corchorifolius L. f. Their structures were identified as ent-kauran-3beta, 16beta, 17, 19-tetrol (1), ent-2-carbonyl-16beta-hydroxy-kauran-17-beta-D-glucoside (2). Compounds 1 and 2 are new compounds.

Hollow PbWO4 nanospindles via a facile sonochemical route.

Novel nanosized lead tungstate (PbWO4) hollow spindles were successfully synthesized, for the first time, via a Pluronic P123- (EO20PO70EO20-) assisted sonochemical process. The triblock copolymer acted as a structure-directing agent and played a key role in the formation of the hollow spindles. An in situ micelle templating mechanism has been proposed for the possible formation mechanism of the hollow nanostructure. The optical properties of the final products were investigated. It is exciting that the as-prepared PbWO4 hollow structure shows extraordinarily high room-temperature photoluminescence intensity compared to the solid structures.

Studies on the effect of dihydromyricetin on antilipid-peroxidation / 中国中药杂志

<p><b>OBJECTIVE</b>To study the effects of Dihydromyricetin (DMY) on antilipid-peroxidation.</p><p><b>METHOD</b>The antilipid-peroxidation of DMY on heart, liver, brain tissue homogenate and mitochondria was measured by the determination of malondiadehyde (MDA) induced by Fe2+ -Vit C, Fe2+ -H2O2, Fe-Cys with TBA spectrometric method.</p><p><b>RESULT</b>DMY could inhibit the lipid peroxidation of homogenate and mitochondria. The inhibition exhibited concentration-dependent manner.</p><p><b>CONCLUSION</b>DMY has good antilipid-peroxidation effect, which is worth studing further.</p>

Studies on chemical constituents in leafs of Ilex kudingcha / 中国中药杂志

<p><b>OBJECTIVE</b>To study chemical constituents of Ilex kudingcha.</p><p><b>METHOD</b>The constituents were isolated by chromatographic method and the structures were identified on the basis of spectral analysis.</p><p><b>RESULT</b>Seven compounds, lupeol(I); 3 beta-hydroxyl-lup-20(29)-ene-24-methyl ester(II); lup-20(29)-ene-3 beta-, 24-diol(III); beta-sitosterol(IV); ursolic acid(V); daucosterol (VI); mannitol were obtained(VII).</p><p><b>CONCLUSION</b>I, III, VI and VII compounds were obtained from genus Ilex for the first time.</p>

Neuropathologic investigation of area tempestas sclerosis in epileptic sensitive rats / 中国应用生理学杂志

<p><b>AIM AND METHODS</b>The relation between AT sclerosis (loss of neurons and proliferation of astrocytes) and long-lasting epileptic susceptibility was investigated by thionine staining, GFAP immunohistochemistry and observing the behavior of rats, after scorpion venom (SV) or normal saline (NS) administrated for three week.</p><p><b>RESULTS</b>Compared with NS+ NS group, both the loss of neurons and proliferation of astrocytes were very marked in KA+ NS group (epileptic susceptible rats) (P < 0.05), but those changes were not visible in KA+ NS group (epileptic nonsusceptible rats).</p><p><b>CONCLUSIONS</b>It suggested that AT sclerosis may be one of important reasons of the long-lasting epileptic susceptibility.</p>

Expression change of P2X_3 receptor in spinal dorsal horn and dorsal root ganglion in inflammatory pain rats / 第三军医大学学报

Objective To investigate the expression change of P2X3 receptor in spinal dorsal horn and dorsal root ganglion(DRG) in rats with experimental inflammatory pain.Methods Totally 30 SD rats received a subcutaneous injection of carrageenan in the right paw to establish inflammatory pain model,and then divided randomly and equally into 5 groups,that is 6,12,24,72 and 168 h after injection.Another 6 rats undergoing a subcutaneous injection of normal saline in the right paw served as control.Pain threshold was assayed by thermal radiation and von Frey filament in 2,4,6,12,24,72 and 168 h after injection.Expression of P2X3 receptor in spinal dorsal horn and DRG of every group was measured by immunohistochemical staining(IHC).Results After injection of carrageenan,thermal hyperalgesia and mechanical allodynia appeared in the rats.The thermal withdrawl latency(TWL) and 50% paw withdrawl threshold(PWT) were decreased obviously from 2 h,descended to the lowest at 12 h,then returned to the normal level after 72 h.The expression of P2X3 receptor in spinal dorsal horn was increased obviously from 24 h,while that at DRG was increased obviously from 12 h.Both of the expressions lasted for 72 h,and returned to the normal level at 168 h after injection.Conclusion Thermal hyperalgesia and mechanical allodynia appear in the rats after carrageenan injection,and the P2X3 receptor is activated and up-regulated in the DRG and spinal cord,suggesting that P2X3 receptor may play an important role in the incidence and development of inflammatory pain.