Purinergic modulation of vascular sympathetic neurotransmission.
Purinergic modulation of vascular sympathetic neurotransmission.
复制标题
血管交感神经传递的嘌呤能调节。
DOI：
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发表时间：
2002
期刊：
影响因子：
--
通讯作者：
M. Kunitomo
中科院分区：
文献类型：
--
作者：
K. Shinozuka;H. Mizuno;Kazuki Nakamura;M. Kunitomo
人们普遍认为，去甲肾上腺素（NE）的释放是通过连接前嘌呤受体的激活来抑制的。我们检查了血管交感神经末梢嘌呤受体的药理学特性和内源性腺苷酸的来源。电（1 Hz）诱发的 NE 释放不仅受到 P1 激动剂的抑制，而且还受到 P2 激动剂的抑制。尽管 P2 激动剂诱导的抑制被 P1 拮抗剂阻断，但 P2 激动剂诱导的抑制并不是由于腺苷的分解。因此，可能存在一类新的嘌呤受体，它被P1-和P2-激动剂激活并被P1-拮抗剂拮抗。除了 NE 之外，8 Hz（而非 1 Hz）的电刺激会引发腺苷酸的释放，例如 ATP、ADP、AMP 和腺苷；并且嘌呤的释放被α1拮抗剂阻断。甲氧明是一种 α1 激动剂，也会引起嘌呤的释放。电（1 Hz）诱发的 NE 释放被甲氧胺抑制，并且这种抑制不仅被 α1 拮抗剂而且还能被 P1 拮抗剂阻断。因此，α1-肾上腺素受体的激活似乎会释放嘌呤，进而通过连接前嘌呤受体抑制 NE 释放。这些结果表明，独特的嘌呤受体和从α1-肾上腺素受体敏感来源释放的内源性嘌呤参与血管交感神经传递的逆向跨突触调节。
It is generally agreed that the release of norepinephrine (NE) is inhibited by activation of prejunctional purinoceptor. We examined the pharmacological properties of purinoceptors on vascular sympathetic nerve terminals and the source of endogenous adenyl purines. Electrically (1 Hz) evoked NE-release was inhibited by not only P1-agonists but also P2-agonists. Although the inhibition induced by P2-agonists was blocked by P1-antagonists, P2-agonists-induced inhibition was not due to the breakdown to adenosine. Therefore, there may be a new class of purinoceptor that is activated by both P1- and P2-agonists and antagonized by P1-antagonists. Electrical stimulation at 8 Hz but not at 1 Hz evoked the release of adenyl purines such as ATP, ADP, AMP and adenosine, in addition to NE; and the purines-release was blocked by an alpha1-antagonist. Methoxamine, an alpha1-agonist, also evoked the release of purines. Electrically (1 Hz)-evoked NE-release was inhibited by methoxamine, and this inhibition was blocked by not only an alpha1-antagonist but also a P1-antagonist. Therefore, the activation of alpha1-adrenoceptor appeared to release purines, which in turn inhibited NE-release via prejunctional purinoceptors. From these results, it is suggested that the unique purinoceptor and the endogenous purines released from alpha1-adrenoceptor-sensitive sources participate in the antidromic transsynaptic modulation of vascular sympathetic neurotransmission.
嘌呤参与甲氧胺释放去甲肾上腺素的调节。
影响因子：
5
作者：
Shinozuka,K;Sedaa,KO;Bjur,RA;Westfall,DP
通讯作者：
Westfall,DP