Effects of Taurine on dysfunction of myocardial nuclear calcium transport in rat myocardial injury induced with isoproterenol / 中国临床药理学与治疗学

Aim To observe the dysfunction of myocardial nuclear calcium transport in rat myocardial injury and effects of taurine on it . Methods The model of myocardial damage was induced by subcutaneous injection of isoproterenol (ISO,5 mg?kg-1?d-1). Myocardial nuclei were purified with Sucrose density centrifugation and identified zymologically. The activity of Ca2+_ATPase was measured zymologically and calcium uptake was assayed with 45Ca2+ isotope.Results Compared with the control, the Ca2+_ATPase activity of myocardial nuclear in ischemia group was decreased by 18.1%(P

Effects of liqustraxin on dysfunction of myocardial nuclear calcium transport / 中国临床药理学与治疗学

AIM: To observe the dysfunciton of myocardial nuclear calcium transport in rat myocardial injury and the effects of liqustraxin on it. METHODS: The model of myocardial damage was induced by subcutaneous injection of isoproterenol (ISO,5 mg?kg -1?d -1). Myocardial nuclei were purified with sucrose density centrifugation and identified zymologically. The activity of Ca 2+-ATPase was measured zymologically and calcium uptake was assayed with 45Ca 2+ isotope. RESULTS: Compared with the control,the Ca 2+-ATPase activity of myocardial nuclear membrane in ischemia group(exprimental) was decreased by 18.1% (P

Effects of Bupivacaine on Calcium Transport Across Biological Membranes and Its Cardiotoxicity / 대한마취과학회지

A new local anesthetic, bupivacaine, is widely used for regional anesthesia because of its high potency and long duration of action. However, bupivacaine is reported to result in cardiovascular collapse associated with convulsion at a plasma concentration above the normal one, while other local anesthetics do not. Also resuscitation is very difficult. Although the mechanism of this action is not known, bupivacaine seems to have an influence on Ca2+ transport across cell membranes via various pathways. The present study was designed to evaluate the effects of bupivacaine on Ca2+ transport across cell membranes. The results are as follows: 1) Bupivacaine inhibites Ca2+ uptake by SR of skeletal muscle. 2) Bupivacaine suppressed the Bowditch and Woodworth staircase phenomena in a guines pig's left auricle, however this was reversible even at convulsant doses. 3) Bupivacaine also suppressed the Na+-Ca2+ exchange pump on guines pig's left auricle. 4) Bupivacaine increased the Ca2+-ATPase activity by SR of skeletal muscle. 5) At concentrations above 3ug/ml, bupivacaine induced cardiac arrhythmia. These findings suggest that bupivacaine-induced cardiotoxicity is possibly due to a Ca2+- channel blockade, depression of the Na+-Ca2+ pump, inhibition of Ca2+ uptake by SR and subsequent decrease of intracellular Ca2+ concentration.

A COMPARISON OF ENZYMATIC ACTIVITIES, Ca~(2+) BINDING AND Ca~(2+) TRANSPORT FUNCTIONS IN SUBCELLULAR MEMBRANE FRACTIONS ISOLATED FROM DOG MESENTERIC ARTERIES AND VEINS / 中国药理学通报

Using subcellular membrane fractions isolated from smooth muscles of dog mesenteric arteries and veins, we compared their enzymatic activities, Ca2+ bindind and Ca2+ transport. The micro-somal (MIC)and plasma membrane(F2) fractions were similarly enriched 4-5 and 10-12 fold respectively in the plasma membrane marker enzymes over the starting membrane mixture. However, MIC and F2 fractions from venous smooth muscle showed higher Mg2+-ATPase activity, slightly increased Ca2+ binding and reduced Ca2+-transport compared to the corresponding fractions from arteries.

Construction and identification of siRNA expression vectors for silencing Ca~(2+) transport protein gene / 中国免疫学杂志

Objective:To construct specific small interfering RNA(siRNA) expressing vectors of intracellular Ca2+ transport protein(CaT1)gene and detect its silencing effects.Methods:The hairpin sequences of siRNAs targeting CaT1 gene were designed,synthesized and cloned into pSlincer 3.1-H1 plasmids after annealing.The vectors were then enriched in E.coli.The recombinant pSlincer 3.1-H1 plasmids were identified by restriction endonuclease cutting and DNA sequencing and then transfected into Human Gastric Carcinoma Cell Line BGC-823.The expression of CaT1 mRNA was examined by RT-PCR.Results:The siRNA oligonucleotides of CaT1 were correctly cloned into the pSlincer 3.1-H1 plasmids and confirmed by restriction endonuclease cutting and DNA sequencing.RT-PCR analysis revealed that the expression of CaT1 mRNA in BGC-823 cells transfected with the pSlincer 3.1-H1 constructs of siRNA was significantly decreased compared with that of the negative control and untransfected group.Conclusion:siRNA expression plasmids for silencing Ca2+ transport protein gene are successfully constructed,and they effectively inhibit the CaT1 gene expression.