EVIDENCE THAT DOPAMINE REGULATES NOREPINEPHRINE SYNTHESIS IN THE RAT SUPERIOR CERVICAL-GANGLION DURING HYPOXIC STRESS
EVIDENCE THAT DOPAMINE REGULATES NOREPINEPHRINE SYNTHESIS IN THE RAT SUPERIOR CERVICAL-GANGLION DURING HYPOXIC STRESS
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DOI：
10.1016/0165-1838(87)90117-2
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发表时间：
1987-03-01
期刊：
影响因子：
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通讯作者：
HANSEN, JT
中科院分区：
文献类型：
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作者：
BROKAW, JJ;HANSEN, JT
已知电刺激节前神经可增加体外大鼠颈上神经节去甲肾上腺素的合成，这一效应似乎部分受非胆碱能递质的调节。在本研究中，我们试图确定交感神经刺激是否也增加了体内大鼠神经节去甲肾上腺素的合成，以及神经节中间神经元释放的多巴胺是否可能调节这一反应。为了解决这些问题，大鼠接受了选择性多巴胺受体阻滞剂螺哌利多的预处理，然后通过暴露于严重的低氧应激进行交感刺激。其余大鼠在低氧暴露前单独给予赋形剂处理。通过测量内源性酪氨酸羟化酶活性和去甲肾上腺素周转率来评估神经节去甲肾上腺素的合成。我们发现，低氧应激增加了去甲肾上腺素合成的这两个指数，但仅在螺哌利多预处理的大鼠中。在用车辆预处理的大鼠中，未检测到这种反应。这些结果表明，交感神经刺激增加了在体大鼠颈上神经节去甲肾上腺素的合成，中间神经元释放的多巴胺可能调节这一反应。
Electrical stimulation of preganglionic nerves is known to increase norepinephrine synthesis in the rat superior cervical ganglion in vitro, an effect which appears to be partially regulated by a non-cholinergic transmitter. In the present study, we sought to determine whether sympathetic stimulation also increases norepinephrine synthesis in the rat ganglion in vivo, and whether dopamine released from ganglionic interneurons might regulate this response. To tackle these questions, rats were pretreated with spiroperidol, a selective dopamine-receptor blocker, and then were sympathetically stimulated by exposure to severe hypoxic stress. Other rats were pretreated with vehicle alone before the hypoxic exposure. Norepinephrine synthesis in ganglia was assessed by measuring endogenous tyrosine hydroxylase activity and norepinephrine turnover. We found that hypoxic stress increased both of these indices of norepinephrine synthesis, but only in rats pretreated with spiroperidol. No such response was detected in rats pretreated with vehicle. These results indicate that sympathetic stimulation increases norepinephrine synthesis in the rat superior cervical ganglion in vivo, and that dopamine released from interneurons might regulate this response.