【摘要】 以炭末胶液在小鼠小肠推进距离占小肠全长的百分数为指标,研究了吗啡耐受对胃肠推进运动的影响。结果如下:(1)吗啡有抑制正常小鼠胃肠推进运动的作用,且随着吗啡剂量的增加,抑制作用逐渐加强。当吗啡剂量为1.25mg/kg 时,推进距离为全小肠的45%,当吗啡剂量增至4倍和16倍时,推进距离分別减少至全小肠的13.5%和6.4% 。(2)吗啡对胃肠推进运动的抑制作用,可因注射纳洛酮而阻断。(3)反复注射吗啡12天,测痛试验表明已产生耐受的动物,吗啡对胃肠推进运动的抑制效应减弱或消失,表明胃肠推进运动也能对吗啡产生耐受。(4)小鼠胃肠对吗啡产生耐受是逐步发展的。从重复注射吗啡4天时起,吗啡对胃肠推进的抑制作用即行减弱,其推进距离为对照组的2.2倍,表明已产生耐受。同法注射吗啡16天,吗啡对胃肠推进运动的抑制作用即消失,推进距离为对照组的11.8倍。但当停止注射吗啡后,胃肠耐受逐渐消退,表明耐受过程是可逆的。更多还原

【Abstract】 Experiments were performed to investigate the effect of morphine tolerance onthe propulsive motility of the gastrointestinal tract in the mice.The distance travelledby the charcoal meal from the pylorus to the caecum was measured after i.v.adminis-tration of morphine.The ratio was expressed as a percentage of the distance travelledby the charcoal meal and the total intestinal length was taken as the index ofpropulsive motility.The results were as follows:1.Morphine inhibited the propulsive motility of the gastrointestinal tract.Thedegree of inhibition was shown to be related with the administered dose of morphine.Thus,the propulsive motility decreased to 45±3.2% after a dose of 1.25 mg/kgof morphine injected.When the dose of morphine was increased 4 and 16folds,the response decreased to 13.5±2.0 % and 6.4±1.4 % respectively.2.The inhibitory effect of morphine on the propulsive motility was blockedby i.v.administration of naloxone.3.When the mice were given increasing doses of morphine subcutaneouslythrice daily for 12 successive days,the inhibitory effect of morphine on thegastrointestinal propulsive motility was reduced or disappeared.These resultsrevealed that the gastrointestinal tract could also be tolerated to morphine.4.The development of gastrointestinal tolerance to morphine was gradual.It took about 4 days of repeated injection of morphine as described above to ob-tain an observable effect.A high degree of tolerance was developed after 16 daysof morphine injection so that the inhibitory effect of morphine on the propul-sive motility was entirely absent.However,this state of morphine tolerance wasladed off gradually after the injection of morphine was stopped.更多还原