Brave S R, Hobbs A J, Gibson A, Tucker J F
Biomedical Sciences Division, King's College London, UK.
Biochem Biophys Res Commun. 1991 Sep 16;179(2):1017-22. doi: 10.1016/0006-291x(91)91920-8.
The interaction between parasympathetic and inhibitory non-adrenergic, non-cholinergic nerves in tracheal smooth muscle was investigated by determining the effects of the NO-synthase inhibitor L-NG-nitro-arginine (L-NOARG) on contractions and the associated acetylcholine release elicited by field stimulation of the muscle. At frequencies above 2Hz contractile responses to field stimulation were potentiated by L-NOARG (50 microM). alpha-chymotrypsin pre-treatment potentiated contractile responses at all frequencies, but the effects of L-NOARG were unaltered. The effect of L-NOARG on responses to 5Hz electrical stimulation was not mimicked by D-NOARG, was reversed by L-, but not D-arginine and was unaffected by epithelium removal. L-NOARG did not affect responses to exogenous acetylcholine nor the overflow of 3H from tissues previously loaded with [3H]-choline. It is therefore concluded that field stimulation of tracheal smooth muscle induces the release of an endogenous nitrate, which, by an inhibitory action on smooth muscle, functionally antagonises the concomitantly released parasympathetic neurotransmitter.
通过测定一氧化氮合酶抑制剂L-NG-硝基精氨酸（L-NOARG）对气管平滑肌收缩以及由该肌肉的场刺激引发的相关乙酰胆碱释放的影响，研究了副交感神经与抑制性非肾上腺素能、非胆碱能神经在气管平滑肌中的相互作用。在频率高于2Hz时，L-NOARG（50微摩尔）增强了对场刺激的收缩反应。α-糜蛋白酶预处理在所有频率下均增强了收缩反应，但L-NOARG的作用未改变。D-NOARG未模拟L-NOARG对5Hz电刺激反应的影响，L-精氨酸可逆转该影响，而D-精氨酸则不能，且去除上皮不影响该作用。L-NOARG不影响对外源性乙酰胆碱的反应，也不影响先前用[3H]-胆碱加载的组织中3H的溢出。因此得出结论，气管平滑肌的场刺激诱导内源性硝酸盐的释放，该硝酸盐通过对平滑肌的抑制作用，在功能上拮抗伴随释放的副交感神经递质。
