摘要
目的:观察选择性A_1受体激动剂环戊腺苷(CPA)对异丙肾上腺素(Iso)诱发的豚鼠乳头状肌后除极和触发活动的影响.方法:应用Iso 50 nmoi·L^(-1)诱发稳定而可重复的早发和迟发后除极(EAD和DAD).用玻璃微电极技术记录EAD和DAD诸参数.结果:CPA能明显地缓解Iso诱发的豚鼠乳状肌早发后除极、迟发后除极和触发活动.8-苯茶碱和格列苯脲能拮抗CPA对Iso诱发早发和迟发后除极的抑制作用.结论:ATP敏感性钾通道参与了Iso诱发的早发和迟发后除极以及CPA对Iso诱发的两种后除极的抑制作用.
AIM:To investigate the effects of N6-cyclopentyladenosine (CPA, selective adeno-sine A1 receptor agonist) on afterdepolar-izations and triggered activity induced by iso-proterenol (Iso) in guinea pig papillary muscle. METHODS: The stable and reproducible early afterdepolarization (EAD) and delayed afterdepolarizaiton (DAD) of guinea pig papillary muslce were induced by Iso 50 nmol.L-1. The parameters of EAD and DAD were recorded using intracellular microelec-trodes. RESULTS: CPA markedly attenuated the development of EAD, DAD, and triggered activity (TA) induced by Iso in guinea pig papillary muscle. The inhibitory effects of CPA on Iso-induced EAD and DAD were antagonized by 8-phenyltheophylline ( 8-PT) and glibenclamide (Gli ). CONCLUSION: ATP-sensitive K+ channels were involved in Iso-induced EAD and DAD, and in the inhibitory effects of CPA on EAD and DAD.
出处
《中国药理学报》
CSCD
1995年第2期163-168,共6页
Acta Pharmacologica Sinica
基金
Project supported by the Natural Science Foundation of Hebei Province, №393125.
关键词
腺苷
异丙肾上腺素
茶碱
格列苯脲
乳头状肌
adenosine
catecholamines
theophylline
glyburide
papillary muscles
electrophysiology
