Sympathetic nervous system-dependent vasoconstriction in humans. Evidence for mechanistic role of endogenous purine compounds.
Sympathetic nervous system-dependent vasoconstriction in humans. Evidence for mechanistic role of endogenous purine compounds.
复制标题
人类交感神经系统依赖性血管收缩。
作者：
S. Taddei;Roberto Pedrinelli;Antonio Salvetti
嘌呤类化合物调节交感神经传递；这种调节通过刺激突触前抑制性腺苷受体（一种被茶碱拮抗的作用）减少神经放电，并通过刺激突触后ATP受体引起血管收缩。在人体中，我们评估了以100微克/100毫升/分钟的速度注入肱动脉的局部茶碱对施加下体负压引起的小动脉交感血管收缩的影响。用应变式静脉体积描记仪测量前臂血流变化。茶碱在这种剂量下减弱了腺苷（P1嘌呤受体的生理激动剂）的血管舒张作用，显著增加了下体负压介导的血管收缩。为了评估与去甲肾上腺素不同的神经递质是否参与茶碱的血管收缩作用，我们在苯氧苄胺存在的情况下重复了之前的实验，以60微克/100毫升/分钟的剂量输注苯氧苄胺，以消除去甲肾上腺素的血管收缩作用。此外，在α -肾上腺素受体阻断后，茶碱继续增加交感血管收缩。我们的数据证实，嘌呤能受体和神经递质也参与人类内源性交感血管收缩。
Purine compounds modulate sympathetic neurotransmission; this modulation decreases nervous discharge by stimulating presynaptic inhibitory adenosine receptors, an effect antagonized by theophylline, and causes vasoconstriction through the stimulation of postsynaptic ATP receptors. In humans we evaluated the effect of local theophylline, which was infused into the brachial artery at the rate of 100 micrograms/100 cc/min, on the arteriolar sympathetic vasoconstriction induced by applying a lower-body negative pressure. Forearm blood flow changes were measured by strain-gauge venous plethysmography. Theophylline, which at this dosage blunted the vasodilator effect of adenosine (the physiological agonist for the P1 purinoceptor), significantly increased lower-body negative pressure-mediated vasoconstriction. To evaluate whether neurotransmitters different from norepinephrine participate in the vasoconstrictor effect of theophylline, we repeated the previous experiment in the presence of phenoxybenzamine, which was infused at a dose (60 micrograms/100 cc/min) that abolished the vasoconstrictor effect of norepinephrine. Also, after alpha-adrenoceptor blockade, theophylline continued to increase sympathetic vasoconstriction. Our data confirm that purinergic receptors and neurotransmitters also participate in endogenous sympathetic vasoconstriction in humans.
腺苷在去甲肾上腺素能神经传递中的作用。
DOI：
10.1152/ajpheart.1988.255.2.h386
发表时间：
1988
期刊：
The American journal of physiology
影响因子：
--
作者：
Kuan,CJ;Jackson,EK
通讯作者：
Jackson,EK