Mechanism mediating nitric oxide-induced inhibition in human jejunal longitudinal smooth muscle.
Mechanism mediating nitric oxide-induced inhibition in human jejunal longitudinal smooth muscle.
复制标题
介导一氧化氮诱导的人空肠纵向平滑肌抑制的机制。
DOI：
10.1067/msy.2001.116414
复制
发表时间：
2001
期刊：
影响因子：
--
通讯作者：
Sarr,MG
中科院分区：
文献类型：
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作者：
Zyromski,NJ;Duenes,JA;Kendrick,ML;Balsiger,BM;Farrugia,G;Sarr,MG
背景肠道神经传递是一个涉及包括一氧化氮(NO)在内的多种神经递质的复杂过程。为探讨一氧化氮(NO)在正常人空肠纵行平滑肌中的作用及其机制(S)，我们在器官室内研究了人胃旁路手术后获得的正常人空肠跨壁条。在竞争性NO合成酶抑制剂NG-氨基-L-精氨酸(1H-[1，2，4]-oxadiazaolo-[4，3-a]-quinoxalin-1-one-NNA，10−3mol/L)和特异性鸟苷酸环化酶抑制剂ODQ的存在和不存在的情况下，观察外源性NO(7×10−6mol/L~7×10−5mol/L)和电场刺激(内源性神经递质的非特异性释放)对自发收缩活动和预收缩肌条(P物质，10−5mol/L)的影响。10−5mol/L和10−4mol/L)。结果外源性NO呈剂量依赖性抑制自发性收缩和松弛预收缩的肌条。在ODQ存在下，NO的作用明显减弱或完全被抑制。非肾上腺素、非胆碱能条件下的电场刺激也能抑制自发性收缩和松弛预收缩的肌条；在ODQ和L-NA的存在下，这两种作用都被减弱，但不是完全被抑制。结论SNO是人空肠纵向平滑肌的一种内源性抑制性神经递质，至少部分是通过鸟苷酸环化酶介导的机制起作用的。其他(非氮能)非肾上腺素能、非胆碱能抑制性神经递质可能在人类肠道的这一部分活跃。
BACKGROUNDEnteric neurotransmission is a complex process involving multiple neurotransmitters, including nitric oxide (NO). Our aim was to evaluate the role and mechanism(s) of action of NO in normal human jejunal longitudinal smooth muscle.METHODSTransmural strips of normal human jejunum obtained from subjects undergoing gastric bypass were studied in organ chambers. Effects of exogenous NO (7 × 10−6mol/L to 7 × 10−5mol/L) and electrical field stimulation (nonspecific release of endogenous neurotransmitters) on spontaneous contractile activity and on precontracted muscle strips (substance P, 10−5mol/L) were evaluated in the presence and absence of the competitive NO synthase inhibitor NG-amino-L-arginine (L-NNA, 10−3mol/L) and the specific soluble guanylyl cyclase inhibitor 1H-[1,2,4]-oxadiazaolo-[4,3-a]-quinoxalin-1-one (ODQ, 10−5mol/L and 10−4mol/L).RESULTSExogenous NO dose-dependently inhibited spontaneous contractility and relaxed precontracted smooth muscle strips. The effects of NO were markedly attenuated or completely inhibited in the presence of ODQ. Electric field stimulation under nonadrenergic, noncholinergic conditions also inhibited spontaneous contractility and relaxed precontracted smooth muscle strips; both of these effects were attenuated, but not completely inhibited, in the presence of both ODQ and L-NNA.CONCLUSIONSNO is an endogenous inhibitory neurotransmitter in human jejunal longitudinal smooth muscle, acting at least in part via a mechanism mediated by guanylyl cyclase. Other (non-nitrergic) nonadrenergic, noncholinergic inhibitory neurotransmitters are likely active in this portion of the human gut.