TRPV4 is not the molecular sensor for bacterial lipopolysaccharides-induced calcium signaling.

Lipopolysaccharides (LPS) is one of the most potent pathogen-associated signals for the immune system of vertebrates. In addition to the canonical pathway of LPS detection mediated by toll-like receptor 4 (TLR4) signaling pathway, TRP channel-mediated pathways endow sensory neurons and epithelial cells with the ability to detect and react to bacterial endotoxins. Previous work revealed that LPS triggers TRPV4-dependent calcium influx in urothelial cells (UCs) and mouse tracheobronchial epithelial cells (mTEC). In marked contrast, here we show that most subtypes of LPS could not directly activate TRPV4 channel. Although LPS from Salmonella enterica serotype Minnesota evoked a [Ca2+]i response in freshly isolated human bronchial epithelial cells (ECs), freshly isolated mouse ear skin single-cell suspensions, or HEK293T cells transiently transfected with mTRPV4, this activation occurred in a TRPV4-independent manner. Additionally, LPS from either E. coli strains or Salmonella enterica serotype Minnesota did not evoke significant difference in inflammation and pain hyperalgesia between wild type and TRPV4 deficient mice. In summary, our results demonstrate that in vitro and in vivo effects induced by LPS are independent of TRPV4, thus providing a clarity to the questioned role of LPS in TRPV4 activation.

Quercetin relieved diabetic neuropathic pain by inhibiting upregulated P2X4 receptor in dorsal root ganglia.

The upregulation of nociceptive ion channels expressed in dorsal root ganglia (DRG) contributes to the development and retaining of diabetic pain symptoms. The flavonoid quercetin (3,3',4',5,7-pentahydroxyflavone) is a component extracted from various fruits and vegetables and exerts anti-inflammatory, analgesic, anticarcinogenic, antiulcer, and antihypertensive effects. However, the exact mechanism underlying quercetin's analgesic action remains poorly understood. The aim of this study was to investigate the effects of quercetin on diabetic neuropathic pain related to the P2X4 receptor in the DRG of type 2 diabetic rat model. Our data showed that both mechanical withdrawal threshold and thermal withdrawal latency in diabetic rats treated with quercetin were higher compared with those in untreated diabetic rats. The expression levels of P2X4 messenger RNA and protein in the DRG of diabetic rats were increased compared with the control rats, while quercetin treatment significantly inhibited such enhanced P2X4 expression in diabetic rats. The satellite glial cells (SGCs) enwrap the neuronal soma in the DRG. Quercetin treatment also lowered the elevated coexpression of P2X4 and glial fibrillary acidic protein (a marker of SGCs) and decreased the upregulation of phosphorylated p38 mitogen-activated protein kinase (p38MAPK) in the DRG of diabetic rats. Quercetin significantly reduced the P2X4 agonist adenosine triphosphate-activated currents in HEK293 cells transfected with P2X4 receptors. Thus, our data demonstrate that quercetin may decrease the upregulation of the P2X4 receptor in DRG SGCs, and consequently inhibit P2X4 receptor-mediated p38MAPK activation to relieve the mechanical and thermal hyperalgesia in diabetic rats.

Downregulation of P2Y12 in the superior cervical ganglia alleviates abnormal sympathetic activity after myocardial ischemia.

Superior cervical ganglia (SCG) innervate the myocardium and participate in sympathoexcitatory transmission. P2Y12 receptor is expressed in satellite glial cells (SGCs). This study seeks to clarify whether the P2Y12 receptor is involved in the sympathoexcitation reflex after myocardial ischemia (MI). MI model was induced by occlusion of the left coronary artery. P2Y12 were assayed by real time PCR and Western blotting. Our results showed that expression levels of P2Y12 mRNA and protein were significantly higher in the MI group than in the sham group. Administration of P2Y12 short hairpin RNA (shRNA) caused downregulation of the P2Y12 receptor in the SCG. In MI rats plus P2Y12 shRNA treatment group, the abnormal changes in diastolic blood pressure (DBP), systolic blood pressure (SBP), heart rate (HR), electrocardiograms (ECGs), and cardiac tissue structures were alleviated. When the treatment of P2Y12 shRNA in MI rats, upregulated co-expression values of P2Y12 and glial fibrillary acidic protein (GFAP), the upregulation of tumor necrosis factor α (TNF-α) and phosphorylated P38 mitogen activated protein kinase (p-P38 MAPK) in the SCG were decreased. Downregulation of the P2Y12 receptor in the SCG after MI may improve cardiac function by alleviating the sympathoexcitatory reflex.

P2Y12 shRNA treatment decreases SGC activation to relieve diabetic neuropathic pain in type 2 diabetes mellitus rats.

Diabetic neuropathic pain is a common complication of type 2 diabetes mellitus (DM). Activation of satellite glial cells (SGCs) in the dorsal root ganglia (DRG) plays a crucial role in neuropathic pain through the release of proinflammatory cytokines. The P2Y12 receptor is expressed in SGCs of the DRG. In this study, our aim was to investigate the role of the P2Y12 receptor on the pathological changes in diabetic neuropathic pain. The present study showed that diabetic neuropathic pain increased mechanical and thermal hyperalgesia in type 2 DM model rats. The results showed that the expression levels of P2Y12 messenger RNA (mRNA) and protein in DRG SGCs were increased in DM model rats compared with control rats. Glial fibrillary acidic protein (GFAP) and interleukin-1ß (IL-1ß) expression levels in the DRG were increased in DM rats. Upregulation of GFAP is a marker of SGC activation. Targeting the P2Y12 receptor by short hairpin RNA (shRNA) decreased the upregulated expression of P2Y12 mRNA and protein, coexpression of P2Y12 and GFAP, the expression of GFAP, IL-1ß, and tumor necrosis factor-receptor 1 in the DRG of DM rats, and relieved mechanical and thermal hyperalgesia in DM rats. After treatment with the P2Y12 receptor shRNA, the enhancing integrated OPTICAL density (IOD) ratios of p-P38 MAPK to P38 mitogen activated protein kinase (MAPK) in the DM rats treated with P2Y12 shRNA were significantly lower than that in the untreated DM rats. Therefore, P2Y12 shRNA treatment decreased SGC activation to relieve mechanical and thermal hyperalgesia in DM rats.

P2Y12 receptor upregulation in satellite glial cells is involved in neuropathic pain induced by HIV glycoprotein 120 and 2',3'-dideoxycytidine.

The direct neurotoxicity of HIV and neurotoxicity of combination antiretroviral therapy medications both contribute to the development of neuropathic pain. Activation of satellite glial cells (SGCs) in the dorsal root ganglia (DRG) plays a crucial role in mechanical and thermal hyperalgesia. The P2Y12 receptor expressed in SGCs of the DRG is involved in pain transmission. In this study, we explored the role of the P2Y12 receptor in neuropathic pain induced by HIV envelope glycoprotein 120 (gp120) combined with ddC (2',3'-dideoxycytidine). A rat model of gp120+ddC-induced neuropathic pain was used. Peripheral nerve exposure to HIV-gp120+ddC increased mechanical and thermal hyperalgesia in gp120+ddC-treated model rats. The gp120+ddC treatment increased expression of P2Y12 receptor mRNA and protein in DRG SGCs. In primary cultured DRG SGCs treated with gp120+ddC, the levels of [Ca2+]i activated by the P2Y12 receptor agonist 2-(Methylthio) adenosine 5'-diphosphate trisodium salt (2-MeSADP) were significantly increased. P2Y12 receptor shRNA treatment inhibited 2-MeSADP-induced [Ca2+]i in primary cultured DRG SGCs treated with gp120+ddC. Intrathecal treatment with a shRNA against P2Y12 receptor in DRG SGCs reduced the release of pro-inflammatory cytokines, decreased phosphorylation of p38 MAPK in the DRG of gp120+ddC-treated rats. Thus, downregulating the P2Y12 receptor relieved mechanical and thermal hyperalgesia in gp120+ddC-treated rats.

Resveratrol-decreased hyperalgesia mediated by the P2X7 receptor in gp120-treated rats.

Background Chronic pain is a common symptom in human immunodeficiency virus (HIV)-1 infection/acquired immunodeficiency syndrome patients. The literature shows that the HIV envelope glycoprotein 120 (gp120) can directly cause hyperalgesia by stimulating primary sensory afferent nerves. The P2X7 receptor in the dorsal root ganglia (DRG) is closely related to neuropathic and inflammatory pain. In this study, we aimed to explore the effect of resveratrol (RES) on gp120-induced neuropathic pain that is mediated by the P2X7 receptor in the rat DRG. Results Mechanical hyperalgesia in rats treated with gp120 was increased compared with that in the sham group. The P2X7 expression levels in rats treated with gp120 were higher than those in the sham group. Co-localization of the P2X7 receptor and glial fibrillary acidic protein (GFAP, a marker of satellite glial cells [SGCs]) in the DRG SGCs of the gp120 group exhibited more intense staining than that of the sham group. RES decreased the mechanical hyperalgesia and P2X7 expression levels in gp120 treatment rats. Co-localization of the P2X7 receptor and GFAP in the gp120+ RES group was significantly decreased compared to the gp120 group. RES decreased the IL-1ß and TNF-α receptor (R) expression levels and ERK1/2 phosphorylation levels as well as increased IL-10 expression in the DRG of gp120-treated rats. Whole cell clamping demonstrated that RES significantly inhibited adenosine triphosphate-activated currents in HEK293 cells that were transfected with the P2X7 plasmid. Conclusions RES relieved mechanical hyperalgesia in gp120-treated rats by inhibiting the P2X7 receptor.

Co-expression changes of lncRNAs and mRNAs in the cervical sympathetic ganglia in diabetic cardiac autonomic neuropathic rats.

Cardiac autonomic neuropathy in Type 2 diabetes (T2D) is often a devastating complication. Long non-coding RNAs (lncRNAs) have important effects on both normal development and disease pathogenesis. In this study, we explored the expression profiles of some lncRNAs involved in inflammation which may be co-expressed with messenger RNA (mRNA) in superior cervical and stellate ganglia after type 2 diabetic injuries. Total RNA isolated from 10 pairs of superior cervical and stellate ganglia in diabetic and normal male rats was hybridized to lncRNA arrays for detections. Pathway analysis indicated that the most significant gene ontology (GO) processes that were upregulated in diabetes were associated with immune response, cell migration, defense response, taxis, and chemotaxis. The Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway revealed that most of the target genes of the lncRNAs were located in cytokine-cytokine receptor interactions, the chemokine signaling pathway and cell adhesion molecules, which were involved in T2D. Gene co-expression network construction showed that the co-expression network in the experimental rats consisted of 268 regulation edges among 105 lncRNAs and 11 mRNAs. Our studies demonstrated the co-expression profile of lncRNAs and mRNAs in diabetic cardiac autonomic ganglia, suggesting possible roles for multiple lncRNAs as potential targets for the development of therapeutic strategies or biomarkers for diabetic cardiac autonomic neuropathy. © 2016 Wiley Periodicals, Inc.

Nanoparticle-encapsulated emodin decreases diabetic neuropathic pain probably via a mechanism involving P2X3 receptor in the dorsal root ganglia.

Diabetic peripheral neuropathy (DPN) is the most common complication of diabetes mellitus (DM). More than 90% of all cases of DM belong to type 2 diabetes mellitus (T2DM). Emodin is the main active component of Radix et rhizoma rhei and has anti-bacterial, anti-viral, anti-ulcerogenic, anti-inflammatory, and anti-cancer effects. Nanoparticle encapsulation of drugs is beneficial for drug targeting and bioavailability as well as for lowering drug toxicity side effects. The aim of this study was to investigate the effects of nanoparticle-encapsulated emodin (nano emodin) on diabetic neuropathic pain (DNP) mediated by the Purin 2X3 (P2X3) receptor in the dorsal root ganglia (DRG). Mechanical withdrawal threshold (MWT) and thermal withdrawal latency (TWL) values in T2DM rats were lower than those of control rats. MWT and TWL in T2DM rats treated with nano emodin were higher compared with those in T2DM rats. Expression levels of P2X3 protein and messenger RNA (mRNA) in the DRG of T2DM rats were higher than those of controls, while levels in T2DM rats treated with nano emodin were significantly lower than those of the T2DM rats. Phosphorylation and activation of ERK1/2 in the T2DM DRG were decreased by nano emodin treatment. Nano emodin significantly inhibited currents activated by the P2X3 agonist α,ß-meATP in HEK293 cells transfected with the P2X3 receptor. Therefore, nano emodin treatment may relieve DNP by decreasing excitatory transmission mediated by the DRG P2X3 receptor in T2DM rats.

The effect of sinomenine in diabetic neuropathic pain mediated by the P2X3 receptor in dorsal root ganglia.

Type 2 diabetes mellitus (T2DM) accounts for more than 90% of all cases of diabetes mellitus (DM). Diabetic neuropathic pain (DNP) is a common complication of T2DM. Sinomenine is a natural bioactive component extracted from the Sinomenium acutum and has anti-inflammatory effects. The aim of our study was to investigate the effects of sinomenine on DNP mediated by the P2X3 receptor in dorsal root ganglia (DRG). The mechanical withdrawal threshold (MWT) and thermal withdrawal latency (TWL) in T2DM rats were lower than those of control rats. MWT and TWL in T2DM rats treated with sinomenine were higher compared with those in T2DM rats. The expression levels of the P2X3 protein and mRNA in T2DM rat DRG were higher compared with those of the control, while those in T2DM rats treated with sinomenine were significantly lower compared with those of the T2DM rats. Sinomenine significantly inhibited P2X3 agonist ATP-activated currents in HEK293 cells transfected with the P2X3 receptor. Sinomenine decreased the phosphorylation and activation of P38MAPK in T2DM DRG. Therefore, sinomenine treatment may suppress the up-regulated expression and activation of the P2X3 receptor and relieve the hyperalgesia potentiated by the activation of P38MAPK in T2DM rats.

LncRNA NONRATT021972 siRNA normalized the dysfunction of hepatic glucokinase through AKT signaling in T2DM rats.

Hepatic glucokinase (GK) expression and activity are decreased in type 2 diabetes mellitus (T2DM), and glycogen synthase kinase-3 (GSK-3) inhibits the synthesis of GK. In hepatocytes, the activation of the protein kinase B (PKB/AKT) signaling pathway enhances GK expression and inhibits the phosphorylation of GSK-3ß. The dysfunction of certain long noncoding RNAs (lncRNAs) has been associated with a variety of diseases. AIMS: This study explored the effects of the lncRNA NONRATT021972 small interfering RNA (siRNA) on the dysfunction of hepatic GK through AKT signaling in T2DM rats. METHODS: Livers from type 2 diabetic rats and hepatocytes cultured in high glucose and high fatty acid media were studied. The changes in expression of AKT, GK and GSK 3ß were detected by western blotting or RT-PCR. The application of bioinformatics technology (CatRAPID) was used to identify the targets of NONRATT021972 RNA. RESULTS: We found that lncRNA NONRATT021972 levels in the liver were increased in type 2 diabetic rats, and the increase was associated with an increase in the blood glucose levels. The NONRATT021972 siRNA enhanced phospho-AKT (p-AKT) levels, GK expression and hepatic glycogen synthesis. This siRNA also reduced phospho-glycogen synthase kinase-3ß (p-GSK-3ß) levels and hyperglycemia in T2DM rats, as well as in hepatocytes cultured in high glucose media with fatty acids. CatRAPID predicted that there was the interaction between NONRATT021972 and p-AKT. CONCLUSIONS: LncRNA NONRATT021972 siRNA may have beneficial effects on T2DM.

Gender Differences and Correlated Factors of Heroin Use Among Heroin Users.

BACKGROUND: Gender differences in illicit drug use are becoming increasingly recognized. However, there are few studies concerning differences between male and female heroin users in China. OBJECTIVES: The study aimed to explore gender differences in terms of socio-demographic characteristics, drug-related behaviors, and treatment history among a heroin-using population in China. METHODS: A cross-sectional study was conducted in four cities in December 2013. A total of 788 participants were recruited from several types of sites in each city: compulsory detoxification centers, methadone maintenance treatment clinics, and detention facilities. The data were collected via a self-administered questionnaire. Analysis of variance, chi-square test, and multivariate logistic regression analyses were conducted to examine gender differences in socio-demographic characteristics, drug-related behaviors, and treatment history. RESULTS: Female heroin users were more likely to be unemployed, have more education, and use heroin with their spouse/companion (p <.05). Male heroin users were more likely to be in detention facilities and MMT clinics, and relapse when they felt hopeless (p <.05). Conclusions/Importance: Although there were some similarities between male and female heroin users, significant gender differences do exist in some aspects of socio-demographic characteristics and heroin use. The data provide evidence that interventions aimed at preventing the initiation of heroin use and reducing relapse should take gender into account.

Long noncoding NONRATT021972 siRNA normalized abnormal sympathetic activity mediated by the upregulation of P2X7 receptor in superior cervical ganglia after myocardial ischemia.

Previous studies showed that the upregulation of the P2X7 receptor in cervical sympathetic ganglia was involved in myocardial ischemic (MI) injury. The dysregulated expression of long noncoding RNAs (lncRNAs) participates in the onset and progression of many pathological conditions. The aim of this study was to investigate the effects of a small interfering RNA (siRNA) against the NONRATT021972 lncRNA on the abnormal changes of cardiac function mediated by the up-regulation of the P2X7 receptor in the superior cervical ganglia (SCG) after myocardial ischemia. When the MI rats were treated with NONRATT021972 siRNA, their increased systolic blood pressure (SBP), diastolic blood pressure (DBP), heart rate (HR), low-frequency (LF) power, and LF/HF ratio were reduced to normal levels. However, the decreased high-frequency (HF) power was increased. GAP43 and tyrosine hydroxylase (TH) are markers of nerve sprouting and sympathetic nerve fibers, respectively. We found that the TH/GAP43 value was significantly increased in the MI group. However, it was reduced after the MI rats were treated with NONRATT021972 siRNA. The serum norepinephrine (NE) and epinephrine (EPI) concentrations were decreased in the MI rats that were treated with NONRATT021972 siRNA. Meanwhile, the increased P2X7 mRNA and protein levels and the increased p-ERK1/2 expression in the SCG were also reduced. NONRATT021972 siRNA treatment inhibited the P2X7 agonist BzATP-activated currents in HEK293 cells transfected with pEGFP-P2X7. Our findings suggest that NONRATT021972 siRNA could decrease the upregulation of the P2X7 receptor and improve the abnormal changes in cardiac function after myocardial ischemia.

LncRNA uc.48+ is involved in diabetic neuropathic pain mediated by the P2X3 receptor in the dorsal root ganglia.

Some long non-coding RNAs (lncRNAs) participate in physiological processes that maintain cellular and tissue homeostasis, and thus, the dysregulated expression of lncRNAs is involved in the onset and progression of many pathological conditions. Research has indicated that the genetic knockout of some lncRNAs in mice resulted in peri- or postnatal lethality or developmental defects. Diabetes mellitus (DM) is a major cause of peripheral neuropathy. Our studies showed that the expression levels of lncRNA uc.48+ in the diabetic rat dorsal root ganglia (DRG) and the DM patients' serum samples were increased. It suggested that lncRNA uc.48+ was involved in the pathophysiological process of DM. The aim of this study was to investigate the effects of lncRNA uc.48+ small interfering RNA (siRNA) on diabetic neuropathic pain (DNP) mediated by the P2X3 receptor in the DRG. The values of the mechanical withdrawal threshold (MWT) and thermal withdrawal latency (TWL) were measured by the von Frey test and Hargreaves' test, respectively. The levels of P2X3 protein and messenger RNA (mRNA) in the DRG were detected by reverse transcription-polymerase chain reaction (RT-PCR), immunohistochemistry, and western blotting. The experiments showed that the MWT and TWL values in DM rats were lower than those in the control rats. The MWT and TWL values in DM rats treated with lncRNA uc.48+ siRNA were increased compared to those in DM rats, but there was no significant difference between the DM rat group and the DM + scramble siRNA group. The levels of P2X3 protein and mRNA in the DM DRG were higher than those in the control, while the levels of P2X3 protein and mRNA in the DG of DM rats treated with uc.48+ siRNA were significantly decreased compared to those in DM rats. The expression levels of TNF-α in the DRG of DM rats treated with uc.48+ siRNA were significantly decreased compared to those in the DM group. The phosphorylation and activation of ERK1/2 in the DM DRG were decreased by uc.48+ siRNA treatment. Therefore, uc.48+ siRNA treatment may alleviate the DNP by inhibiting the excitatory transmission mediated by the P2X3 receptor in DRG.

Estrogen metabolites increase nociceptor hyperactivity in a mouse model of uterine pain.

Pain emanating from the female reproductive tract is notoriously difficult to treat, and the prevalence of transient pelvic pain has been placed as high as 70%-80% in women surveyed. Although sex hormones, especially estrogen, are thought to underlie enhanced pain perception in females, the underlying molecular and cellular mechanisms are not completely understood. Here, we showed that the pain-initiating TRPA1 channel was required for pain-related behaviors in a mouse model of estrogen-induced uterine pain in ovariectomized female mice. Surprisingly, 2- and 4-hydroxylated estrogen metabolites (2- and 4-HEMs) in the estrogen hydroxylation pathway, but not estrone, estradiol, or 16-HEMs, directly increased nociceptor hyperactivity through TRPA1 and TRPV1 channels, and picomolar concentrations of 2- and 4-hydroxylation estrone (2- or 4-OHE1) could sensitize TRPA1 channel function. Moreover, both TRPA1 and TRPV1 were expressed in uterine-innervating primary nociceptors, and their expression was increased in the estrogen-induced uterine pain model. Importantly, pretreatment with 2- or 4-OHE1 recapitulated estrogen-induced uterine pain-like behaviors, and intraplantar injections of 2- and 4-OHE1 directly produced a TRPA1-dependent mechanical hypersensitivity. Our findings demonstrated that TRPA1 is critically involved in estrogen-induced uterine pain-like behaviors, which may provide a potential drug target for treating female reproductive tract pain.

Quality of Life and Its Correlates in Alcohol Use Disorder Patients With and Without Depression in China.

Objective: Alcohol use disorder (AUD) is a serious issue worldwide and frequently co-occurs with depression. However, the quality of life (QOL) of AUD patients with and without depression is not well studied in the Chinese Han population. The aim of this study was to investigate QOL and its correlates in AUD patients with and without depression in China. Methods: Five hundred and fifteen psychiatric patients diagnosed with AUD were recruited. All these patients completed the Beck Depression Inventory (BDI) to assess depression, the Medical Outcome Study 36-Item Short Form Health Survey (SF-36) to evaluate QOL and the Alcohol Use Disorders Identification Test (AUDIT) to measure the severity of drinking. Results: Compared with AUD patients without depression, those with depression had a lower QOL in all eight domains of the SF-36 (all P < 0.001), but were more willing to have alcohol-related treatment (P < 0.05). Negative correlations were noted between (i) the BDI total score and all eight domains of the SF-36 (all P < 0.001); and (ii) between the AUDIT total score and six domains of the SF-36 (all P < 0.05). Conclusions: Depression impairs QOL in patients with AUD in China. Early intervention in comorbid depression to improve QOL is needed.

Prevalence, Demographic, and Clinical Correlates of Comorbid Depressive Symptoms in Chinese Psychiatric Patients With Alcohol Dependence.

BACKGROUND: Depressive symptoms are common among psychiatric patients with alcohol dependence (AD). However, the prevalence and clinical correlates of comorbid depressive symptoms are less well studied in Chinese Han patients. METHODS: In this hospital-based survey, we recruited 378 psychiatric patients diagnosed with AD according to the Diagnostic and Statistical Manual of Mental Disorders-Fourth Edition (DSM-IV). All patients completed the Beck Depression Inventory (BDI) to evaluate depressive symptoms and the Alcohol Use Disorders Identification Test (AUDIT) to assess the severity of drinking. RESULTS: Compared to patients without depressive symptoms, 48.9% (185/378) of the patients with comorbid depressive symptoms were younger, had a more unstable marital status, had a higher AUDIT total score, and had a higher adverse consequences subscore (all P < 0.05). Further logistic regression analysis showed that unstable marital status (Odds ratios [OR] = 2.20, 95% confidence interval [CI] 1.21-3.99) and AUDIT total score (OR=1.07, 95% CI 1.03-1.11) were significantly associated with depressive symptoms. CONCLUSIONS: Our findings indicate high comorbidity between AD and depressive symptoms in Chinese psychiatric patients. Moreover, some variables are correlates of comorbid depressive symptoms. Particular attention should be paid to the early detection and intervention for this comorbid condition and its risk factors.

The Inhibition by Guanfu Base A of Neuropathic Pain Mediated by P2Y12 Receptor in Dorsal Root Ganglia.

Activation of satellite glial cells (SGCs) in the dorsal root ganglia (DRG) is involved in mechanical and thermal hyperalgesia. The upregulated P2Y12 receptor expressed in SGCs of the DRG participates in the nociceptive transmission of neuropathic pain. Guanfu base A (GFA) has been reported to exhibit antiarrhythmic and anti-inflammatory effects. In this study, we explored the effects of GFA on P2Y12 receptor-mediated mechanical and thermal hyperalgesia in chronic constriction injury (CCI) rats. Sprague-Dawley rats were randomly divided into sham operation group (Sham), CCI operation group (CCI), CCI rats treated with guanfu base A group (CCI + GFA) and control rats treated with GFA group (Ctrl + GFA). Mechanical withdrawal threshold and thermal withdrawal latency were measured. P2Y12 expression in L4-L6 dorsal root ganglion (DRG) was detected by quantitative real-time PCR and Western blot. After CCI treatment, mechanical and thermal hyperalgesia and the expression values of P2Y12 receptor mRNA and protein in DRG were increased. Dual-labeling immunofluorescence showed that the coexpression of P2Y12 receptor and glial fibrillary acidic protein (GFAP) in the DRG of CCI rats was increased compared to sham rats. GFA relieved mechanical and thermal hyperalgesia in the CCI rats, decreased the expression of P2Y12 mRNA and protein and phosphorylation of p38 MAPK in the DRG, and increased the ADP-downregulated cAMP concentrations in HEK293 cells transfected with P2Y12 plasmid. After CCI rats were treated with GFA, the coexpression of P2Y12 receptor and GFAP in the DRG was significantly decreased compared to the untreated CCI group. Thus, downregulating the P2Y12 receptor relieved mechanical and thermal hyperalgesia in the CCI rats.