【摘要】 观察大鼠侧脑室注射P物质 (SP)及药物对胃电 机械活动和体表胃电活动 (EGG)的影响 ,应用SP受体拮抗剂和阿托品 (atropine)探讨SP的受体机制 ;比较了冷应激后胃对SP和SP受体拮抗剂的动力学反应性的变化。雄性Wistar大鼠 4 4只 ,随机分为 7组 :正常对照 ;SP ;SP受体拮抗剂 ;atropine ;冷应激对照 ;冷应激 +SP ;冷应激 +SP拮抗剂。结果表明 :(1)侧脑室SP给药 10 μL ,(10 -8mol/L)能引起胃窦运动明显增强 (P <0 0 5 ) ,(2 )应激使胃运动幅度极显著升高、频率加快 (P <0 0 1) ,应激后大鼠对侧脑室注入P物质的胃动力学反应性较前明显增强 (P <0 0 5 )。(3)侧脑室注入SP受体拮抗剂 ([D Pro2 ,D Phe7,D Trp9] SubstanceP) 10 μL ,(10 -8mol/L)在确定SP的神经递质作用中没有明显作用。侧脑室注射M受体阻断剂atropine10 μL ,(1× 10 -7mol/L)不能阻断脑内P物质对胃的收缩效应 ,结果提示 ,中枢注入的P物质可以促进胃电 机械活动的调节因子参与中枢增强胃肠的调控 ;SP在中枢可能是通过第二信使而发挥兴奋性递质作用的更多还原

【Abstract】 Absrtact: We observed the effect of intracerebral ventricular administration of exogenous substanceP (SP) on gastric electromechanical action and abdominal electrogastrography (EGG), and investigated the receptor mechanisms of SP through application of SP receptor antagonists and atropine. We also identified the change in gastrokinetic reaction to SP and SP receptor antagonist after cold stress. 44 male Wistar rats were divided into 7 groups as normal control, SP, SP antagonist, Atropine, cold stress control, cold stress+SP and cold stress+SP antagonist. The results showed that: (1) Intracerebral ventricular administration of SP10 μL, (10 -8 mol/L) significantly enhanced movement of gastric sinus( P <0.05). (2) Cold stress increaced the amplitude and frequency of gastric movement. The gastrokinetic reaction to intracerebral ventricular injection of SP in rats was significantly improved after stress when compared with the control ( P <0.05). (3) It seems that intraventricular administration of SP receptor antagonist does not prove the role of SP as a neurotransmitter. Intracerebral ventricular injection of M receptor blocker, Atropine10 μL, (1×10 -7 mol/L), failed to block the gastric contraction effect of cerebral substance P. So, the results indicated that the substance P, which was injected into the central nervous system played a role in regulation of gastrointestinal movement by the centrum as a regulator through improvement of gastric electromechanical action. The effect of SP as a stimulating transmitter in the centrum may be expressed through the second messengers.更多还原