Haskó G, Elenkov I J, Vizi E S
Institute of Experimental Medicine, Hungarian Academy of Sciences, Budapest.
Immunol Lett. 1995 Jul-Aug;47(1-2):133-7. doi: 10.1016/0165-2478(95)00085-j.
In a previous study we have shown that, in response to electrical stimulation, there is a substantial release of noradrenaline (NA) from the sympathetic nerve terminals of the rat thymus which is of axonal, vesicular origin. In the present study neurochemical evidence was obtained that the release of NA is subject to presynaptic modulation. This modulation operates through stimulation of alpha 2B-adrenoreceptors, N-nicotinic, P1-purinergic and prostaglandin E2 presynaptic receptors. Through these receptors the release of NA, i.e., the message from the central nervous system to the thymus, can be affected by endogenous ligands or drugs. A novel, potent and highly selective competitive antagonist of the alpha 2-adrenoreceptor, CH-38083, significantly enhanced the release of NA, suggesting that its release in the thymus is under tonic inhibitory control exerted by endogenously released NA. Since adrenoreceptors on thymocytes involved in the modulation of certain thymocyte functions have recently been described, it is suggested that the presynaptic modulation of the release of NA in the thymus is involved in neuro-immune communication.
在先前的一项研究中，我们已经表明，对大鼠胸腺交感神经末梢进行电刺激时，会有大量去甲肾上腺素（NA）从轴突、囊泡来源释放出来。在本研究中，获得了神经化学证据，表明NA的释放受到突触前调节。这种调节通过刺激α2B -肾上腺素能受体、N -烟碱型、P1 -嘌呤能和前列腺素E2突触前受体起作用。通过这些受体，NA的释放，即从中枢神经系统到胸腺的信息传递，可以受到内源性配体或药物的影响。一种新型、强效且高度选择性的α2 -肾上腺素能受体竞争性拮抗剂CH - 38083显著增强了NA的释放，这表明其在胸腺中的释放受到内源性释放的NA施加的紧张性抑制控制。由于最近已经描述了参与某些胸腺细胞功能调节的胸腺细胞上的肾上腺素能受体，因此有人提出胸腺中NA释放的突触前调节参与了神经 - 免疫通讯。
