Vilain P, Emonds-Alt X, Le Fur G, Brelière J C
Sanofi Recherche, Montpellier, France.
Can J Physiol Pharmacol. 1997 Jun;75(6):587-90.
In vitro tachykinin-induced contractions of guinea pig ileum longitudinal smooth muscle were investigated under isometric conditions by using selective agonists ([Sar9,Met(O2)11]substance P, [Nle10]neurokinin A-(4-10), senktide) and antagonists (SR 140333, SR 48968, SR 142801), respectively, for the tachykinin NK1, NK2, and NK3 receptors. [Sar9,Met(O2)11]Substance P (10 nM) induced a tonic contraction with superimposed phasic contractions. Both tonic and phasic muscular activities were completely abolished by SR 140333 (10 nM) and were not modified by SR 142801 (10 nM). SR 48968 (10 nM) and atropine (0.001 mM) did not modify the tonic muscular activity but inhibited the phasic muscular activity. [Nle10]Neurokinin A-(4-10) (10 nM) only caused a phasic contractile response that was inhibited by SR 48968. Atropine, SR 140333, and SR 142801 were without effect. Senktide (1 nM) induced combined tonic and phasic contractile responses. SR 142801 blocked the phasic and tonic muscular activities, whereas SR 48968 and SR 140333 were inactive. After addition of atropine, only tonic contractile response was abolished. These results showed fundamental differences in isometric tonic and phasic contractile responses of guinea pig ileum longitudinal smooth muscle to tachykinins.
在等长条件下，分别使用速激肽NK1、NK2和NK3受体的选择性激动剂（[Sar9,Met(O2)11]P物质、[Nle10]神经激肽A-(4-10)、senktide）和拮抗剂（SR 140333、SR 48968、SR 142801），研究了豚鼠回肠纵行平滑肌的体外速激肽诱导收缩。[Sar9,Met(O2)11]P物质（10 nM）诱导出强直收缩并伴有叠加的相性收缩。SR 140333（10 nM）完全消除了强直和相性肌肉活动，而SR 142801（10 nM）对其无影响。SR 48968（10 nM）和阿托品（0.001 mM）不改变强直肌肉活动，但抑制相性肌肉活动。[Nle10]神经激肽A-(4-10)（10 nM）仅引起相性收缩反应，该反应被SR 48968抑制。阿托品、SR 140333和SR 142801对此无作用。Senktide（1 nM）诱导出联合的强直和相性收缩反应。SR 142801阻断了相性和强直肌肉活动，而SR 48968和SR 140333无活性。加入阿托品后，仅强直收缩反应被消除。这些结果表明豚鼠回肠纵行平滑肌对等长强直和相性收缩反应的速激肽存在根本差异。
