AIM: To investigate the effect of selective Cyclooxygenase-2 (COX-2) inhibitor 4-[5-(4-Chloro-phenyl)-3- (trifluoromethyl)- 1H-pyrazol- 1-yl] benzenesulfonamide (SC-236), on the cholecystokinin (CCK)-octape...AIM: To investigate the effect of selective Cyclooxygenase-2 (COX-2) inhibitor 4-[5-(4-Chloro-phenyl)-3- (trifluoromethyl)- 1H-pyrazol- 1-yl] benzenesulfonamide (SC-236), on the cholecystokinin (CCK)-octapeptideinduced acute pancreatitis (AP) in rats. METHODS: Wistar rat weighing 240 g to 260 g were divided into three groups. (1) Normal DMSO treated group, (2) SC-236 at 4 mg/kg treated group; SC-236 systemically administered via the intravenous (i.v.) catheter, followed by 75 μg/kg CCK octapeptide subcutaneously three times, after 1, 3 and 5 h. This whole procedure was repeated for 5 d. (3) Dimethyl sulfoxide (DMSO) treated group: an identical protocol was used in this group as in the SC-236 cohort (see 2. above). Repeated CCK octapeptide treatment resulted in a typical experimentally induced pancreatitis in the Wistar rats. RESULTS: SC-236 improved the severity of CCK- octapeptide-induced AP as measured by laboratory criteria [the pancreatic weight/body weight (p.w/ b.w) ratio, the level of serum amylase and lipase]. The SC-236 treated group showed minimal histologic evidence of pancreatitis and a significant reduction in myeloperoxidase activity. SC-236 also increased heat shock protein (HSP)-60 and HSP72 compared with the DMSO-treated group in the CCK-octapeptide-induced AP and also reduced the pancreatic levels of COX-2. Furthermore, SC-236 reduced proinflammatory cytokine synthesis and inhibited NF-KB activation compared with the DMSO-treated group in the CCK-octapeptide-induced AP. CONCLUSION: Our results suggested that COX-2 plays pivotal role in the development of AP and COX-2 inhibitors may play a beneficial role in preventing AP.展开更多
Serotonin (5-HT) has been found to stimulate meiotic maturation of oocytes in many molluscs. During maturation, several signaling pathways are involved, especially the phosphatidylinositol and cAMP pathways. In order ...Serotonin (5-HT) has been found to stimulate meiotic maturation of oocytes in many molluscs. During maturation, several signaling pathways are involved, especially the phosphatidylinositol and cAMP pathways. In order to examine the possible role of the phosphatidylinositol signaling pathway in regulating oocyte maturation in Mercenaria mercenaria, the effects of the activator/inhibitor of phospholipase (PLC) and protein kinase C (PKC) on serotonin-induced maturation were studied. Results show that high-concentrations of neomycin (inhibitor of PLC) blocked oocyte maturation, while 9, 10-dimethyl-1, 2-benzanthracene (DMBA, activator of PLC) promoted oocyte maturation in the presence of serotonin. It was also found that in the presence of serotonin, phorbol 12-myristate 13-acetate (PMA, activator of PKC) inhibited oocyte maturation, while sphingosine (inhibitor of PKC) stimulated oocyte maturation. These results indicate that serotonin-induced oocyte maturation requires the activation of the phosphatidylinositol pathway. Decrease of PLC inhibited serotonin-induced oocyte maturation, whereas a decrease of PKC stimulated the maturation. Thus, our study indicates that serotonin promotes maturation of M. mercenaria oocytes through PLC stimulated increase in calcium ion concentration via inositol-1, 4, 5-trisphosphate (IP3) but not PKC.展开更多
基金Supported by the Ministry of Science & Technology/Korea Science & Engineering Foundation through the Vestibuloco-chlear Research Center at Wonkwang University, No. R13-2002- 055-00000-0
文摘AIM: To investigate the effect of selective Cyclooxygenase-2 (COX-2) inhibitor 4-[5-(4-Chloro-phenyl)-3- (trifluoromethyl)- 1H-pyrazol- 1-yl] benzenesulfonamide (SC-236), on the cholecystokinin (CCK)-octapeptideinduced acute pancreatitis (AP) in rats. METHODS: Wistar rat weighing 240 g to 260 g were divided into three groups. (1) Normal DMSO treated group, (2) SC-236 at 4 mg/kg treated group; SC-236 systemically administered via the intravenous (i.v.) catheter, followed by 75 μg/kg CCK octapeptide subcutaneously three times, after 1, 3 and 5 h. This whole procedure was repeated for 5 d. (3) Dimethyl sulfoxide (DMSO) treated group: an identical protocol was used in this group as in the SC-236 cohort (see 2. above). Repeated CCK octapeptide treatment resulted in a typical experimentally induced pancreatitis in the Wistar rats. RESULTS: SC-236 improved the severity of CCK- octapeptide-induced AP as measured by laboratory criteria [the pancreatic weight/body weight (p.w/ b.w) ratio, the level of serum amylase and lipase]. The SC-236 treated group showed minimal histologic evidence of pancreatitis and a significant reduction in myeloperoxidase activity. SC-236 also increased heat shock protein (HSP)-60 and HSP72 compared with the DMSO-treated group in the CCK-octapeptide-induced AP and also reduced the pancreatic levels of COX-2. Furthermore, SC-236 reduced proinflammatory cytokine synthesis and inhibited NF-KB activation compared with the DMSO-treated group in the CCK-octapeptide-induced AP. CONCLUSION: Our results suggested that COX-2 plays pivotal role in the development of AP and COX-2 inhibitors may play a beneficial role in preventing AP.
基金Supported by the National High Tecnhology Research and Development Program of China (863 Program) (No. 2004AA603810)
文摘Serotonin (5-HT) has been found to stimulate meiotic maturation of oocytes in many molluscs. During maturation, several signaling pathways are involved, especially the phosphatidylinositol and cAMP pathways. In order to examine the possible role of the phosphatidylinositol signaling pathway in regulating oocyte maturation in Mercenaria mercenaria, the effects of the activator/inhibitor of phospholipase (PLC) and protein kinase C (PKC) on serotonin-induced maturation were studied. Results show that high-concentrations of neomycin (inhibitor of PLC) blocked oocyte maturation, while 9, 10-dimethyl-1, 2-benzanthracene (DMBA, activator of PLC) promoted oocyte maturation in the presence of serotonin. It was also found that in the presence of serotonin, phorbol 12-myristate 13-acetate (PMA, activator of PKC) inhibited oocyte maturation, while sphingosine (inhibitor of PKC) stimulated oocyte maturation. These results indicate that serotonin-induced oocyte maturation requires the activation of the phosphatidylinositol pathway. Decrease of PLC inhibited serotonin-induced oocyte maturation, whereas a decrease of PKC stimulated the maturation. Thus, our study indicates that serotonin promotes maturation of M. mercenaria oocytes through PLC stimulated increase in calcium ion concentration via inositol-1, 4, 5-trisphosphate (IP3) but not PKC.