Serotonin receptor 2B induces visceral hyperalgesia in rat model and patients with diarrhea-predominant irritable bowel syndrome

BACKGROUND Serotonin receptor 2B(5-HT2B receptor)plays a critical role in many chronic pain conditions.The possible involvement of the 5-HT2B receptor in the altered gut sensation of irritable bowel syndrome with diarrhea(IBS-D)was investigated in the present study.AIM To investigate the possible involvement of 5-HT2B receptor in the altered gut sensation in rat model and patients with IBS-D.METHODS Rectosigmoid biopsies were collected from 18 patients with IBS-D and 10 patients with irritable bowel syndrome with constipation who fulfilled the Rome IV criteria and 15 healthy controls.The expression level of the 5-HT2B receptor in colon tissue was measured using an enzyme-linked immunosorbent assay and correlated with abdominal pain scores.The IBS-D rat model was induced by intracolonic instillation of acetic acid and wrap restraint.Alterations in visceral sensitivity and 5-HT2B receptor and transient receptor potential vanilloid type 1(TRPV1)expression were examined following 5-HT2B receptor antagonist adminis-tration.Changes in visceral sensitivity after administration of the TRPV1 antago-INTRODUCTION Irritable bowel syndrome(IBS)is a chronic functional bowel disorder characterized by recurrent abdominal pain with altered bowel habits that affects approximately 15%of the population worldwide[1].IBS significantly impacts the quality of life of patients.Although the pathogenesis of IBS is not completely understood,the role of abnormal visceral sensitivity in IBS has recently emerged[2,3].5-Hydroxytryptamine(5-HT)is known to play a key role in the physiological states of the gastrointestinal tract.Plasma 5-HT levels in IBS with diarrhea(IBS-D)patients were greater than those in healthy controls[4],suggesting a possible role of 5-HT in the pathogenesis of IBS-D.The serotonin receptor 2(5-HT2 receptor)family comprises three subtypes:5-HT2A,5-HT2B,and 5-HT2c.All 5-HT2 receptors exhibit 46%-50%overall sequence identity,and all of these receptors preferentially bind to Gq/11 to increase inositol phosphates and intracellular calcium mobilization[5].5-HT2B receptors are widely expressed throughout the gut,and experimental evidence suggests that the primary function of 5-HT2B receptors is to mediate contractile responses to 5-HT through its action on smooth muscle[6].The 5-HT2B receptor is localized to both neurons of the myenteric nerve plexus and smooth muscle in the human colon.The 5-HT2B receptor mediates 5-HT-evoked contraction of longitudinal smooth muscle[6].These findings suggest that the 5-HT2B receptor could play an important role in modulating colonic motility,which could affect sensory signaling in the gut.Other laboratories have shown that the 5-HT2B receptor participates in the development of mechanical and formalin-induced hyperalgesia[7,8].A 5-HT2B receptor antagonist reduced 2,4,6-trinitrobenzene sulfonic acid(TNBS)and stress-induced visceral hyperalgesia in rats[9,10].However,the role of the 5-HT2B receptor in IBS-D patients and in acetic acid-and wrap restraint-induced IBS-D rat models was not investigated.

Are TrkB receptor agonists the right tool to fulfill the promises for a therapeutic value of the brain-derived neurotrophic factor?

Brain-derived neurotrophic factor signaling via its receptor tro pomyosin receptor kinase B regulates several crucial physiological processes.It has been shown to act in the brain,promoting neuronal survival,growth,and plasticity as well as in the rest of the body where it is involved in regulating for instance aspects of the metabolism.Due to its crucial and very pleiotro pic activity,reduction of brain-derived neurotrophic factor levels and alterations in the brain-derived neurotrophic factor/tropomyosin receptor kinase B signaling have been found to be associated with a wide spectrum of neurological diseases.Howeve r,because of its poor bioavailability and pharmacological properties,brain-derived neurotrophic factor itself has a very low therapeutic value.Moreover,the concomitant binding of exogenous brain-derived neurotrophic factor to the p75 neurotrophin receptor has the potential to elicit several unwanted and deleterious side effects.Therefo re,developing tools and approaches to specifically promote tropomyosin receptor kinase B signaling has become an important goal of translational research.Among the newly developed tools are different categories of tropomyosin receptor kinase B receptor agonist molecules.In this review,we give a comprehensive description of the diffe rent tro pomyosin receptor kinase B receptor agonist drugs developed so far and of the res ults of their application in animal models of several neurological diseases.Moreover,we discuss the main benefits of tropomyosin receptor kinase B receptor agonists,concentrating especially on the new tropomyosin receptor kinase B agonist antibodies.The benefits observed both in vitro and in vivo upon application of tropomyosin receptor kinase B receptor agonist drugs seem to predominantly depend on their general neuroprotective activity and their ability to promote neuronal plasticity.Moreover,tro pomyosin receptor kinase B agonist antibodies have been shown to specifically bind the tropomyosin receptor kinase B receptor and not p75 neurotrophin receptor.Therefore,while,based on the current knowledge,the tropomyosin receptor kinase B receptor agonists do not seem to have the potential to reve rse the disease pathology per se,promoting brainderived neurotrophic factor/tro pomyosin receptor kinase B signaling still has a very high therapeutic relevance.

Leukocyte immunoglobulin-like receptor B2:A promising biomarker for colorectal cancer

According to the latest global cancer statistics,colorectal cancer(CRC)has emerged as the third most prevalent malignant tumor across the globe.In recent decades,the medical field has implemented several levels of CRC screening tests,encompassing fecal tests,endoscopic examinations,radiological examinations and blood tests.Previous studies have shown that leukocyte immunoglobulin-like receptor B2(LILRB2)is involved in inhibiting immune cell function,immune evasion,and promoting tumor progression in acute myeloid leukemia and nonsmall cell lung cancer.However,its interaction with CRC has not been reported yet.Recently,a study published in the World Journal of Gastroenterology revealed that LILRB2 and its ligand,angiopoietin-like protein 2,are markedly overexpressed in CRC.This overexpression is closely linked to tumor progression and is indicative of a poor prognosis.The study highlights the potential of utilizing the concentration of LILRB2 in serum as a promising biomarker for tumors.However,there is still room for discussion regarding the data processing and analysis in this research.

Endothelin receptor antagonists for the treatment of diabetic nephropathy:A meta-analysis and systematic review

BACKGROUND Diabetic nephropathy(DN)is the main cause of chronic kidney disease and endstage renal disease worldwide.Although available clinical trials have shown that endothelin receptor(ER)antagonists may be a novel and beneficial drug for DN,no consistent conclusions regarding their sufficient effectiveness and safety for patients with DN have been presented.AIM To assess the effectiveness and safety of ER antagonists among patients with DN.METHODS The EMBASE,PubMed,MEDLINE,Cochrane,and ClinicalTrials.gov databases were searched without any language restrictions.Relative risks with 95%confidence intervals(CIs)for dichotomous data and mean differences or standardized mean difference with 95%CIs for continuous data were calculated using Review Manager 5.3 software.Publication bias was assessed using Egger’s test with Stata/SE software.RESULTS We enrolled seven studies with six data sets and 5271 participants.The ER antagonists group showed a significantly greater reduction in albuminuria and more patients with 40%reduction in urinary albumin-to-creatinine ratio than the control group(P<0.0001 and P=0.02,respectively).Subgroup analysis for reductions in estimated glomerular filtration rate(eGFR)showed that for the middle-dosage subgroup,the ER antagonists group exhibited lower eGFR reduction than the control group(P<0.00001;mean difference,0.7095%CI:0.66,0.74).Moreover,significant reductions in systolic and diastolic blood pressure were observed in the invention group.CONCLUSION ER blockades combined with angiotensin converting enzyme inhibitor/angiotensin II type 1 receptor blockers may be an effective treatment to lower blood pressure and reduce proteinuria in DN with declined eGFR.However,attention should be given to adverse events,including cardiac failure,anemia,and hypoglycemia,as well as serious adverse events.

Correlation between Pulmonary Endothelin Receptors and Alveolar-arterial Oxygen Gradient in Rats with Hepatopulmonary Syndrome

The correlation between pulmonary endothelin receptors and alveolar-arterial oxygen gradient （A aDO2） in rats with hepatopulmonary syndrome was investigated. Animals were divided into 2 groups： Sham operated （Sham） group and common bile duct ligation （CBDL） group. Arterial blood gas was evaluated by a blood gas analyzer. The concentrations of ET-1 in blood and lung tissue sample were evaluated by radioimmunoassay. The distribution and expression of two kinds of subtype receptor of ET-1, ETRA and ETRB were examined by in situ hybridization. The results showed that the level of A aDO2, was higher in CBDI. group than that in Sham group （P〈0.05）. The levels of plasma and pulmonary ET-1 in CBDL group were both higher than in Sham group （P〈0.05 ）. There was no significant difference in average A of ETRA between two groups by imaging analysis （0.21±0.06 vs 0.22±0.08, P〉0.05）, while that of ETRB was higher in CBDI. group than in Sham group （0.58±0.16 vs 0.28±0.07, P〈0.05）. The expression of ETRBinlung was positively correlated with A aDO2（P〈0.05）. It was concluded that the widened A-aDO2 may be related with enhancement of the expression of ETRB in lung.

Leukocyte immunoglobulin-like receptor B2 overexpression as a promising therapeutic target and noninvasive screening biomarker for colorectal cancer

BACKGROUND Colorectal cancer(CRC)has become the second most deadly malignancy in the world,and the exploration of screening markers and precise therapeutic targets is urgent.Our previous research identified leukocyte immunoglobulin-like receptor B2(LILRB2)protein as a characteristic protein of CRC,but the association between LILRB2 expression and clinicopathological features,the internal mechanism related to CRC progression,and screening diagnostic efficacy are not clear.Therefore,we hypothesized that LILRB2 is significantly highly expressed in CRC tissues,correlated with advanced stage and a poor prognosis,and could be used as a therapeutic target and potential screening biomarker for CRC.AIM To explore whether LILRB2 can be used as a potential therapeutic target and noninvasive screening biomarker for CRC.METHODS Patients who underwent radical surgery for CRC at China-Japan Friendship Hospital between February 2021 and October 2022 were included.Cancer and paracancerous tissues were collected to verify LILRB2 expression,and the association between LILRB2 expression and clinicopathological features was analysed.Serum was collected from CRC patients,adenoma patients and healthy controls during the same period to assess the diagnostic value of LILRB2 as a noninvasive screening biomarker,and its diagnostic value was further compared with that of the traditional markers carcinoembryonic antigen(CEA)and carbohydrate antigen 19-9(CA19-9).RESULTS A total of 58 CRC patients were included,and LILRB2 protein was significantly overexpressed in cancer tissues compared with paracancerous tissues(P<0.001).Angiopoietin-like protein 2(ANGPTL2)protein,as the ligand of LILRB2,was synergistically overexpressed in CRC tissues(P<0.001),and overexpression of LILRB2 and ANGPTL2 protein was significantly correlated with poor to moderate differentiation,vascular involvement,lymph node metastasis,distant metastasis,advanced tumor-node-metastasis stage and a poor prognosis(P<0.05),which suggested that LILRB2 and ANGPTL2 are closely associated with CRC progression.In addition,serum LILRB2 concentrations increased stepwise in healthy individuals,adenoma patients and CRC patients with statistically significant differences.The sensitivity of serum LILRB2 for the diagnosis of CRC was 89.74%,the specificity was 88.89%,the area under the curve was 0.95,and the diagnostic efficacy was better than that of conventional CEA and CA19-9.CONCLUSION LILRB2 protein can be used as a potential novel therapeutic target and noninvasive screening biomarker for CRC,which is beneficial for early screening and precise treatment.

Increased endothelin receptor B and G protein coupled kinase-2 in the mesentery of portal hypertensive rats

AIM: To elucidate the mechanisms of mesenteric vasodilation in portal hypertension (PHT), with a focus on endothelin signaling. METHODS: PHT was induced in rats by common bile duct ligation (CBDL). Portal pressure (PP) was measured directly via catheters placed in the portal vein tract. The level of endothelin-1 (ET-1) in the mesenteric circulation was determined by radioimmunoassay, and the expression of the endothelin A receptor (ETAR) and endothelin B receptor (ETBR) was assessed by immunofluorescence and Western blot. Additionally, expression of G protein coupled kinase-2 (GRK2) and β-arrestin 2, which influence endothelin receptor sensitivity, were also studied by Western blot. RESULTS: PP of CBDL rats increased significantly (11.89 ± 1.38 mmHg vs 16.34 ± 1.63 mmHg). ET-1 expression decreased in the mesenteric circulation 2 and 4 wk after CBDL. ET-1 levels in the systemic circulation of CBDL rats were increased at 2 wk and decreased at 4 wk. There was no change in ETAR expression in response to CBDL; however, increased expression of ETBR in the endothelial cells of mesenteric arterioles and capillaries was observed. In sham-operated rats, ETBR was mainly expressed in the CD31+ endothelial cells of the arterioles. With development of PHT, in addition to the endothelial cells, ETBR expression was noticeably detectable in the SMA+ smooth muscle cells of arterioles and in the CD31+ capillaries. Following CBDL, increased expression of GRK2 was also found in mesenteric tissue, though there was no change in the level of β-arrestin 2. CONCLUSION: Decreased levels of ET-1 and increased ETBR expression in the mesenteric circulation following CBDL in rats may underlie mesenteric vasodilation in individuals with PHT. Mechanistically, increased GRK2 expression may lead to desensitization of ETAR, as well as other vasoconstrictors, promoting this vasodilatory effect.

Association of vitamin D and polymorphisms of its receptor with antiviral therapy in pregnant women with hepatitis B

BACKGROUND The interruption of mother-to-child transmission(MTCT)is considered important to decrease the individual and population morbidity of hepatitis B virus(HBV)infection as well as the global burden of hepatitis B.Serum vitamin D(VD)is associated with hepatitis B.AIM To assess whether baseline VD levels and single nucleotide polymorphisms of the VD receptor gene(VDR SNPs)are associated with the efficacy of tenofovir disoproxil fumarate(TDF)in the prevention of MTCT in pregnant women with high HBV viral loads.METHODS Thirty-eight pregnant women who were at high risk for MTCT of HBV(those with an HBV DNA level≥2×10^(5)IU/mL during 12-24 wk of gestation)receiving antiviral therapy of TDF between June 1,2019 and June 30,2021 in Mianyang were included in this retrospective study.The women received 300 mg TDF once daily from gestational weeks 24-28 until 3 mo after delivery.To further characterize the clinical relevance of maternal serum HBV DNA levels,we stratified patients according to HBV DNA level as follows:Those with levels<2×10_(5)(full responder group)vs those levels≥2×10^(5)IU/mL(partial responder group)at delivery.Serum levels of 25-hydroxyvitamin D[25(OH)D],liver function markers,virological parameters,VDR SNPs and other clinical parameters were collected to analyze their association with the efficacy of TDF.The Mann-Whitney U test or t test was used to analyze the serum levels of 25(OH)D in different groups.Multiple linear regressions were utilized to analyze the determinants of the maternal HBV DNA level at delivery.Univariate and multivariate logistic regression analyses were employed to explore the association of targeted antiviral effects with various characteristics at baseline and delivery.RESULTS A total of 38 pregnant women in Mianyang City at high risk for MTCT of HBV were enrolled in the study.The MTCT rate was 0%.No mother achieved hepatitis B e antigen or hepatitis B surface antigen(HBsAg)clearance at delivery.Twenty-three(60.5%)participants were full responders,and 15(39.5%)participants were partial responders according to antiviral efficacy.The present study showed that a high percentage(76.3%)of pregnant women with high HBV viral loads had deficient(<20 ng/mL)or insufficient(≥20 but<31 ng/mL)VD levels.Serum 25(OH)D levels in partial responders appeared to be significantly lower than those in full responders both at baseline(25.44±9.42 vs 17.66±5.34 ng/mL,P=0.006)and delivery(26.76±8.59 vs 21.24±6.88 ng/mL,P=0.044).Serum 25(OH)D levels were negatively correlated with maternal HBV DNA levels[log(10)IU/mL]at delivery after TDF therapy(r=-0.345,P=0.034).In a multiple linear regression analysis,maternal HBV DNA levels were associated with baseline maternal serum 25(OH)D levels(P<0.0001,β=-0.446),BMI(P=0.03,β=-0.245),baseline maternal log10 HBsAg levels(P=0.05,β=0.285)and cholesterol levels at delivery(P=0.015,β=0.341).Multivariate logistic regression analysis showed that baseline serum 25(OH)D levels(OR=1.23,95%CI:1.04-1.44),maternal VDR Cdx2 TT(OR=0.09,95%CI:0.01-0.88)and cholesterol levels at delivery(OR=0.39,95%CI:0.17-0.87)were associated with targeted antiviral effects(maternal HBV DNA levels<2×10^(5) at delivery).CONCLUSION Maternal VD levels and VDR SNPs may be associated with the efficacy of antiviral therapy in pregnant women with high HBV viral loads.Future studies to evaluate the therapeutic value of VD and its analogs in reducing the MTCT of HBV may be justified.

The Expression of Endothelin Receptor B in Melanoma Cells A375 and Sk-mel-1 and the Proliferative Effects of Endothelin 3 on A375 Cells

In order to investigate the expression of endothelin receptor B （ETR-B） in human malignant melanoma （MM） cells A375 and SK-mel-1 and the proliferative effects of endothelin 3 （ET3） on A375 cells, RT-PCR was applied to detect the expression of ETR-B gene in human MM cells A375 and SK-mel-1. MTT method was used to evaluate the growth enhancing effects of ET3 on A375 cell line in vitro. The results showed that ETR-B gene was expressed in both MM A375 and SK-mel-1 cells. ET3 had stronger ability to enhance the proliferation of A375 cells in vitro in a concentration-dependent manner. It was suggested that ET3/ETR-B might play an important proliferative role in MM.

Study of the Effect of Leeching on Plasma Endothelin and Soluble Interleukin-2 Receptor in Patients with Systemic Lupus Erythematosus

Objective: to explore the mechanism of leeching in treating systemic lupus erythematosus (SLE). Methods: Forty-four patients with SLE were randomly divided into conventional corticosteroid treated group (control group, n =20) and conventional treatment group with leeching intervention added (leeching group, n =24). Before and after treatment the concentration of plasma endothelin (ET) and soluble interleukin-2 receptor (sIL-2R) were determined. Results: Before treatment the level of plasma ET and sIL-2R in the SLE patients were all higher than those in the normal healthy group, ( P <0.01). But after treatment the level of these in both groups were significantly improved than those of before treatment ( P <0.05), and comparison between these two treated groups showed that the difference between them was significant ( P <0.05). Conclusion: Leeching added to conventional treatment of SLE could be more effective in improving the level of plasma ET and sIL-2R, and ameliorating the impairment of renal tissues.

Correlation of calcitonin gene-related peptide and endothelin receptor A with subarachnoid hemorrhage

Numerous studies have demonstrated that endothelin-1 combines with endothelin receptor A, resulting in intense vasoconstriction. Although calcitonin gene-related peptide （CGRP） suppresses endothelin-1, CGRP and endothelin receptor A exhibit direct biological effects on brain tissue. The present study analyzed CGRP and endothelin receptor A expression following subarachnoid hemorrhage in rabbits using immunohistochemistry. CGRP expression was significant at 5 days after model establishment, and endothelin receptor A expression was significant at 3 days after model induction. The perimeter of the basilar artery was measured to determine the amount of cerebral vasospasm. Analytical results revealed a significantly shortened basilar artery perimeter following subarachnoid hemorrhage. Changes in the basilar artery perimeter were negatively associated with endothelin receptor A expression, but positively correlated with CGRP expression in vessels. These results suggest that following subarachnoid hemorrhage, CGRP and endothelin receptor A expressions dynamically changed in brain vessels and tissues, although these changes were not synchronous. Changes in endothelin receptor A expression exhibited a significant effect on the occurrence and development of delayed cerebral vasospasm and delayed neuronal death, while CGRP relaxed vessels and protected nerves.

MUTATION OF THE ENDOTHELIN-B RECEPTOR AND THE ENDOTHELIN-3 GENE IN CHINESE SPORADIC CASES OF HIRSCHSPRUNG'S DISEASE

Objective To investigate the mutation of endothelin receptor B (EDNRB) gene and endothelin 3 (EDN 3) gene in sporadic Hirschsprungs disease (HD) in Chinese population. Methods Genomic DNA was extracted from bowel tissues of 34 unrelated HD patients which were removed by surgery. Exon 3, 4, 6 of EDNRB gene and Exon 1, 2 of EDN 3 gene were amplified by polymerase chain reaction (PCR) and analyzed by single strand conformation polymorphism (SSCP).Results EDNRB mutations were detected in 2 of the 13 short segment HDs. One mutant was in the exon 3; the other one was in the exon 6. EDN 3 mutation was detected in 1 of the 13 short segment HDs and in the exon 2. Both EDNRB mutation and EDN 3 mutation were detected in one short segment HD. No mutations were detected in the ordinary or long segment HD. Conclusion The mutations of EDNRB gene and EDN 3 gene are found in the short segment HD of sporadic Hirschsprung's disease in Chinese population, which suggests that the EDNRB gene and EDN 3 gene play important roles in the pathogenesis of HD. the mutations of EDNRB and EDN 3 lead to the maldevelopment of the enteric nervous system.

Synthesis and Crystal Structure of an Endothelin Receptor Antagonist Ambrisentan

The title compound was synthesized and its crystal structure was determined by single-crystal X-ray diffraction. The crystal is of orthorhombic system （C22H22N2O4, Mr = 378.42）, space group P2121 with a = 6.8786（12）, b = 14.259（2）, c = 19.712（3） A, V= 1933.5（6） A3, Z = 4, Dc = 1.300 g/cm3, f（000） = 800, μ= 0.090 mm-1, the final R = 0.0324 and wR = 0.0775 for 2410 observed reflections （I 〉 2σ（I））. The structure, especially the absolute configuration, of the title compound ambrisentan, an important endothelin receptor antagonist, was confirmed by single- crystal X-ray diffraction. The three aromatic rings in the lattice are basically orthogonal to one another. There is an intermolecular hydrogen bond in the crystal, which helps to further stabilize the crystal. One of the two non-classical intramolecular hydrogen bonds can help to stabilize the molecular conformation in the lattice.

Effects of gamma-aminobutyric acid receptors on muscarinic receptor-mediated free calcium ion levels in the facial nucleus following facial nerve injury

Muscarinic receptors and nicotine receptors can increase free calcium ion levels in the facial nucleus via different channels following facial nerve injury. In addition, γ-aminobutyric acid A （GABAA） receptors have been shown to negatively regulate free calcium ion levels in the facial nucleus by inhibiting nicotine receptors. The present study investigated the influence of GABAA, γ-aminobutyric acid B （GABAB） and C （GABAc） receptors on muscarinic receptors in rats with facial nerve injury by confocal laser microscopy. GABAA and GABAB receptors exhibited significant dose-dependent inhibitory effects on increased muscarinic receptor-mediated free calcium ion levels following facial nerve injury. Results showed that GABAA and GABAB receptors negatively regulate muscarinic receptor effects and interplay with cholinergic receptors to regulate free calcium ion levels for facial neural regeneration.

Effects of endothelin B receptor antagonists, BQ788 and ET-1_(11-21) fragment on the bronchoconstriction elicited by isocapnic hyperpnea in guinea pigs

Objective To explore the role of endothelin (ET) in the pathogenesis of exercise induced asthma (EIA), we investigated the effects of ET B receptor antagonists, ET 1 11 21 fragment and N cis 2,6 dimethylpi^peridinocardonyl L γ methylleucyl D 1 methoxycarbonyl tryptophanyl D norleucine (BQ788) on broncho^constriction elicited by isocapnic hyperpnea in guinea pigs Methods Eighteen pathogen free Hartley guinea pigs were randomly divided into three groups A: normal saline (NS) inhalation control group (n=6), B: BQ788 group (n=6), and C: ET 1 11 21 fragment group (n=6) Guinea pigs were anesthetized with pentobarbital sodium After measuring the basal value of lung resistance (R L) and dynamic compliance of the respiratory system (Cdyn), NS (0 96?ml), BQ788 (9?nmol) and ET 1 11 21 fragment (9?nmol) were inhaled A rodent respirator with a dry 5%CO 2-95%O 2 mixture at room temperature provided mechanical ventilation (V T 8?ml/animal, 100 breaths/min) for 5?min R L and Cdyn of the 3 groups were measured again after isocapnic hyperpnea challenge Results In the control group, isocapnic hyperpnea of dry gas elicited a marked increase in R L and decrease in Cdyn R L and Cdyn of the guinea pigs from BQ788 group and ET 1 11 21 fragment group did not change significantly Conclusion It was demonstrated that selective ET B receptor antagonists, ET 1 11 21 fragment and BQ788, inhibited the bronchoconstriction induced by isocapnic hyperpnea in guinea pigs The data showed that ETs are potent constrictors of guinea pig airway smooth muscle via a direct effect on ET receptors It was suggested that ET receptor antagonists, especially ET B receptor antagonist, might be beneficial in preventing EIA

INTRACELLULAR REDISTRIBUTION OF CARDIAC ENDOTHELIN- 1 RECEPTOR IN RAT DURING MYOCARDIAL HYPERTROPHY

Objective. In a model of rat cardiac hypertrophy, the changes in the distribution of ET- 1 receptors in two subcellular fractions, the sarcolemma and the light vesicles during myocardial hypertrophy were studied. Methods. Cardiac hypertrophy was produced by placing a constricting clip around the suprarenal abdominal aorta of rats, and ET- 1 receptor was assayed with radioactive analysis method. Results. It was found that plasma and ventricular ET- 1 levels increased significantly on week 2 and week 4 of pressure overload. ET- 1 binding studies showed that during myocardial hypertrophy, the maximum binding capacity (Bmax) was increased by 41％ (P< 0.01) and 65％ (P< 0.01) in sarcolemma in H- 2 week and H- 4 week groups, but was decreased by 24％ (P< 0.01) and 21％ (P< 0.01) in light vesicles. The sum of Bmax of sarcolemmal and light vesicle fractions was increased by 33％ (P< 0.01) and 57％ (P< 0.01) in group H- 2 week and H- 4 week, respectively. Conclusion. ET- 1 receptors in rat heart were externalized from light vesicles to sarcolemma, which may contribute to the development of myocardial hypertrophy.

Expression of ΔDNMT3B Variants and Its Association with Estrogen/Progestogen Receptor Status in Breast Cancer

Objective： Our previous study has showed that △DNMT3B is the predominant form of DNMT3B in non-small cell lung cancer （NSCLC）. In this study, we aimed to explore the expression patterns of the △DNMT3B variants in breast cancer and to identify whether the pattern was similar to that in NSCLC or not and its clinical significance. Methods： Expression of seven △DNMT3B variants in 59 breast cancer and the corresponding normal tissue was measured using RT-PCR. The correlations between the expressions of △DNMT3B variants and the clinical parameters including ER/PR status, clincopathologic feature and survivals were analyzed. Results： There were significant differences in the expression ratios of △DNMT3B1-7 variants between breast cancer tissues and normal tissues （P〈0.001）. The positive ratio of △DNMT3B1-7 variants were 66%, 71%, 17%, 51%, 76.2%, 50% and 61% in tumor tissue, respectively; while 16%, 8.4%, 3.38%, 3.38%, 11.8%, 13.5% and 5.08% in the corresponding normal tissue, which was different from the pattern of △DNMT3B1-7 expression in NSCLC （62%, 76%, 2.5%, 46%, 18%, 27% and 16% in tumor tissue, respectively; while 18%, 11%, 0%, 3.3%, 0%, 0% and 0% in normal lung tissue, respectively; P〈0.0001）. Expressions of △DNMT3B2, 3B4 and 3B7 were higher in the patients with negative estrogen receptor （ER） than those with positive estrogen receptor （P=0.035, P=0.0141 and P=0.0219, respectively）. △DNMT3B7 expression was higher for the patients with negative progestogen receptor （PR） compared to those with positive progestogen receptor （P=0.0379）. Expression ratio of △DNMT3B5 in stage Ⅲ tumors is lower than that in stage Ⅰ/Ⅱ ones （P= 0.041）. But we did not find any relation between the △DNMT3B variants and the patients＇ survival. Conclusion： The pattern of △DNMT3B variants in breast cancer is different from that in NSCLC. Expressions of △DNMT3B2, 3B4 and 3B7 are associated with estrogen receptors status. While △DNMT3B7 is associated with progestogen receptor. No relation between the △DNMT3B variants and the patients＇ survival were found.

Effects of quadruple antituberculous drugs in combination with linezolid and moxifloxacin on CSF cytology, NSE, NGF and its receptors in patients with refractory tuberculous meningitis

Objective: To investigate the effects of linezolid and moxifloxacin combined with quadruple antituberculosis drugs on CSF cytology, NSE (neuronal specific enolase), NGF(nerve growth facor) and its receptors, endothelin and its receptors and CRP (C reaction protein) in patients with refractory tuberculous meningitis. Method: A total of 56 patients were selected with tuberculous meningitis in our hospital from February 2014 to December 2017,randomly divided them into 2 groups, each group was 28 cases, set as the observation group and the control group, both groups were treated with quadruple antituberculosis drugs, the observation group was given ilinezolid on this basis, and the control group was combined with moxifloxacin, The course of treatment was 4 weeks, compared the levels of CSF cytology, NSE, NGF and NGF receptors, endothelin and endothelin receptors, and CRP after treatment in the two groups. Result:The CSF cytology, NSE, NGF and NGF receptors, endothelin and endothelin receptor, and CRP levels remained unchanged before treatment, the difference was not statistically significant. After treatment, the chloride and glucose levels in the observation group were higher than those before treatment and that of the control group, the protein, white blood cell count, and cerebrospinal fluid pressure levels were lower than before treatment and that of the control group, the difference was statistically significant;The NSE level in the observation group after treatment was lower than before treatment and that of the control group, the difference was statistically significant;After treatment, the levels of NGF and its receptors in the observation group were higher than those before treatment and that of the control group, and the levels of endothelin, and its receptor, CRP were lower than those before treatment and that of the control group, the difference was statistically significant. Conclusion:The use of linezolid in combination with quadruple antituberculosis drugs to treat refractory tuberculous meningitis has better clinical effect, effectively improve cerebrospinal fluid cytology, regulate cerebrospinal fluid NSE levels, restore NGF, endothelin and its receptor function, reduce inflammatory response, recommended for clinical promotion and application.

Influence of baicalin on the expression of receptor activator of nuclear factor-κB ligand and osteoprotegerin in human periodontal ligament cells

Objective To study the effect of baicalin on the expression of receptor activator of nuclear factor-κB ligand(RANKL)and osteoprotegerin(OPG)in cultured human periodontal ligament(HPDL)cells.Methods Small interfering RNA(siRNA)eukaryotic expression vector targeted transforming growth factor βⅡ receptor(TGF-β RⅡ)was constructed and transfected into T cells.HPDL cells with T cells transfected with siRNA or not were placed in the culture medium that had been added with lipopolysaccharide(LPS)and baicalin.The obtained solution was divided into six groups according to the components(group Ⅰ:HPDL cells+LPS+T cells transfected with siRNA1+baicalin;group Ⅱ:HPDL cells+LPS+T cells transfected with siRNA1;group Ⅲ:HPDL cells+LPS+T cells+baicalin;group Ⅳ:HPDL cells+LPS+T cells;group Ⅴ:HPDL cells+baicalin;group Ⅵ:HPDL cells)and was cultured for 48 hours.RT-PCR was used to observe the effect of baicalin on the expression of OPG-RANKL in HPDL cells.Results The ratio of RANKL/OPG in group Ⅰ was lower than that in group Ⅱ(P<0.01)and higher than that in group Ⅲ(P<0.01);The ratio of RANKL/OPG in group Ⅲ was lower than that in group Ⅳ(P<0.01);the ratio of RANKL/OPG in group Ⅳ was higher than that in group Ⅵ(P<0.01);the ratio of RANKL/OPG in group Ⅴ was lower than that in group Ⅵ(P<0.05).Conclusion ① Baicalin could decrease the ratio of RANKL/OPG in HPDL cells.② The TGF-β signaling transduction plays an important role in the effect of baicalin on the RANKL/OPG ratio in HPDL cells.③ Baicalin acts not only through TGF-β to regulate RANKL/OPG in HPDL cells,but also through other pathways.

Effects of endotoxin on endothelin receptor in hepatic and intestinal tissues after endotoxemia in rats

INTRODUCTIONEndothelins(ETs) has a potent and sustainedvasoconstrictive effect on a variety of blood vessels.The vascular smooth muscle cell (VSMC)is thetarget for ETs.VSMC of the whole body containsendothelin receptor (ETR).A great number ofexperiments have shown that three distinctcomplementary DNAs of ETR have been identifiedi.e.,endothelin A receptor(ET_A receptor),endothelin B receptor(ET_B receptor)