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 dimethylp...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展开更多
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...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.展开更多
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 appl...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.展开更多
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 ...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.展开更多
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...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.展开更多
Summary： Endothelin-3 （ET-3） is aberrantly expressed in both metastatic melanoma tissues and cul tured melanoma cells. Our previous work showed that ET-3 could promote survival of metastatic mela noma cells via its...Summary： Endothelin-3 （ET-3） is aberrantly expressed in both metastatic melanoma tissues and cul tured melanoma cells. Our previous work showed that ET-3 could promote survival of metastatic mela noma cells via its altered expression. In this study, we investigated the mechanisms responsible for these gene-induced phenotypes in melanoma cells. An ET-3 gene sequence-specific shRNA vector pLVTHM-ET3-RNAi was constructed and transfected into human malignant melanoma cells A375 and MMRU, and the resultant molecular events and cellular changes were examined. As compared with the empty-vector group, cell proliferation was slowed down, and the growth inhibition rates were 38.9% in A375 cells and 38.4% in MMRU cells after transfection. In addition, cell invasion capability was also inhibited, with a reduction of 62.2% in A375 cells and 54.3% in MMRU cells. The percentage of apoptotic cells was found to increase. Meanwhile, in both cell lines, secreted protein acidic and rich in cy teine （SPARC） levels were down-regulated together with inhibition of its upstream signaling molecule, NF-kB. Thus, the current results suggested that down-regulated expression of ET3 attenuates the ma lignant behaviors of human melanoma ceils partially by decreasing the expression of SPARC and NF-kB.展开更多
文摘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
基金Supported by Grant from National Key New Drug Creation Project of China, No. 2009ZX09102
文摘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.
基金This project was supported by a grant from National Natural Sciences Foundation of China (No 30671891)
文摘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.
基金ThisresearchwassupportedbytheNaturalScienceFoundationofShaanxiProvince (No .2 0 0 0SM 58)
文摘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.
文摘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.
基金supported partially by the grants from the National Natural Science Foundation of China(No.30671891,and No.81072232)the Canadian Foundation for Innovation,and the Canadian Institutes of Health Research(No.CIHR #IMH-37565 and No.MOP-84300)
文摘Summary： Endothelin-3 （ET-3） is aberrantly expressed in both metastatic melanoma tissues and cul tured melanoma cells. Our previous work showed that ET-3 could promote survival of metastatic mela noma cells via its altered expression. In this study, we investigated the mechanisms responsible for these gene-induced phenotypes in melanoma cells. An ET-3 gene sequence-specific shRNA vector pLVTHM-ET3-RNAi was constructed and transfected into human malignant melanoma cells A375 and MMRU, and the resultant molecular events and cellular changes were examined. As compared with the empty-vector group, cell proliferation was slowed down, and the growth inhibition rates were 38.9% in A375 cells and 38.4% in MMRU cells after transfection. In addition, cell invasion capability was also inhibited, with a reduction of 62.2% in A375 cells and 54.3% in MMRU cells. The percentage of apoptotic cells was found to increase. Meanwhile, in both cell lines, secreted protein acidic and rich in cy teine （SPARC） levels were down-regulated together with inhibition of its upstream signaling molecule, NF-kB. Thus, the current results suggested that down-regulated expression of ET3 attenuates the ma lignant behaviors of human melanoma ceils partially by decreasing the expression of SPARC and NF-kB.
