The effects of local anesthetics on intracellular Ca^(2+) release from ryanodine-sensitive Ca^(2+) stores in gerbil hippocampal neurons

To examine the effects of procaine and lidocaine on intracellular Ca 2+ release from sarcoplasmic reticulum ryanodine sensitive Ca 2+ stores Methods The experiment was performed on hippocampal slices from 60-80 g male Mongolian gerbils Levels of intracellular Ca 2+ concentration in the slices were measured by microfluorometry The slices were perfused with 50 mmol/L KCl containing medium for 30 seconds Then, the medium was switched to physiological medium After 5 min of incubation, the slice was perfused with 20 mmol/L caffeine containing physiology medium for 2 min Following incubation, the slice was superfused with physiological medium until the end of the experiment The effects of procaine and lidocanin (100 μmol/L) on caffeine evoked Ca 2+ release were evaluated by adding them to the medium after high K + medium perfusion Results Caffeine induced a marked increase in intracellular Ca 2+ concentration which was then decreased 12% upon the addition of procaine ( P 【0 05); however, lidocaine, did not induce a similar inhibitory reaction Conclusion Procaine inhibits ryanodine receptor mediated Ca 2+ release from intracellular Ca 2+ stores, while lidocaine may inhibit Ca 2+ release through other mechanisms

幽门螺杆菌感染蒙古沙土鼠疾病模型的建立

利用蒙古沙土鼠建立幽门螺杆菌(Helicobacter pylori,Hp)NCTC 11637株胃内感染模型。感染方法有两种,方法Ⅰ是沙土鼠禁食18h后用50%酒精0.5mL预处理,6h后接种Hp,间隔12h、24h分别再次接种。方法Ⅱ的接种方法同方法Ⅰ,但接种后每日口服雷尼替丁(5m g/kg体重)。胃内接种H p后,于第7天、15天、35天、45天分别用Hp抗原酶联免疫诊断试剂盒、细菌培养和胃组织切片的方法观察沙土鼠胃内细菌感染情况和胃病理组织学变化。结果表明,给沙土鼠胃内灌服酒精以损伤胃黏膜并每日口服雷尼替丁,在人工接种35天后,胃内见有多量Hp生长,胃组织病变与Hp自然感染的病例相似。