血管活性肠肽对离体神经支配的豚鼠气管标本中胆碱能神经传递的影响。

The effects of vasoactive intestinal polypeptide on cholinergic neurotransmission in an isolated innervated guinea pig tracheal preparation.

作者信息

Martin J G, Wang A, Zacour M, Biggs D F

机构信息

Meakins-Christie Laboratories, McGill University, Montreal, Quebec, Canada.

出版信息

Respir Physiol. 1990 Feb;79(2):111-21. doi: 10.1016/0034-5687(90)90011-m.

DOI:10.1016/0034-5687(90)90011-m

PMID:2159651

Abstract

To explore the possibility that VIP modulates cholinergic neurotransmission in the airways, we studied the effects of exogenous VIP on contractile responses of an isolated innervated guinea pig tracheal preparation to vagal nerve stimulation (NS), electrical field stimulation (EFS) and exogenous acetylcholine (ACh). VIP (2.5 x 10(-8), 2.5 x 10(-7) M) caused concentration-dependent reductions in responses to NS and EFS. Low frequency stimulations (1 Hz) were significantly more inhibited than higher frequencies (5 and 20 Hz). VIP inhibited NS significantly more than EFS at 1 and 5 but not 20 Hz. In contrast, VIP (2.5 x 10(-7) M) did not significantly reduce responses to ACh (3 x 10(-7), 10(-6), and 3 x 10(-6) M). The neutral endopeptidase inhibitor phosphoramidon (5 x 10(-6) M) enhanced responses of NS to VIP but did not affect responses to NS in the absence of VIP. We conclude that in the isolated guinea pig tracheal preparation, VIP can modulate cholinergic neurotransmission by actions that are predominantly on post-ganglionic nerves but it has also a small additional effect on ganglionic transmission.

摘要

为了探究血管活性肠肽（VIP）调节气道胆碱能神经传递的可能性，我们研究了外源性VIP对分离的有神经支配的豚鼠气管标本对迷走神经刺激（NS）、电场刺激（EFS）和外源性乙酰胆碱（ACh）的收缩反应的影响。VIP（2.5×10⁻⁸、2.5×10⁻⁷ M）使对NS和EFS的反应呈浓度依赖性降低。低频刺激（1 Hz）比高频刺激（5和20 Hz）受到的抑制更显著。在1 Hz和5 Hz时，VIP对NS的抑制作用明显大于对EFS的抑制作用，但在20 Hz时并非如此。相反，VIP（2.5×10⁻⁷ M）并未显著降低对ACh（3×10⁻⁷、10⁻⁶和3×10⁻⁶ M）的反应。中性内肽酶抑制剂磷酰胺素（5×10⁻⁶ M）增强了NS对VIP的反应，但在没有VIP的情况下不影响对NS的反应。我们得出结论，在分离的豚鼠气管标本中，VIP可通过主要作用于节后神经的方式调节胆碱能神经传递，但对神经节传递也有小的额外作用。