间接拟交感神经药酪胺促使大鼠和豚鼠输精管释放内源性三磷酸腺苷。

Release of endogenous ATP from the vasa deferentia of the rat and guinea-pig by the indirect sympathomimetic tyramine.

Kirkpatrick K A, Burnstock G

Department of Anatomy and Developmental Biology, University College London, UK.

J Auton Pharmacol. 1994 Oct;14(5):325-35. doi: 10.1111/j.1474-8673.1994.tb00613.x.

Abstract

Adenosine 5'triphosphate (ATP) as well as [3H]-noradrenaline ([3H]-NA) is released by perfusion of the vas deferens with the indirect sympathomimetic tyramine (100 microM); this result is consistent with the concept of sympathetic cotransmission. 2. While tyramine produced a strong contraction in the vas deferens of the rat, it had little mechanical action in the guinea-pig vas deferens. This appears to be largely because tyramine induces considerably lower levels of release of both ATP and NA from the guinea-pig vas deferens compared to that of the rat. Furthermore, NA released by tyramine appears to release ATP from a secondary pool in the rat vans deferens, but not that of the guinea-pig, since prazosin reduced the tyramine-induced release of ATP in the rat vas deferens. 3. alpha,beta-Methylene ATP (alpha,beta-meATP) increased both the spontaneous release of ATP and the tyramine-evoked efflux of ATP and [3H]-NA. The basal and tyramine-induced efflux of [3H]-NA was also enhanced by the alpha 1-adrenoceptor antagonist, prazosin, suggesting that prejunctional alpha 1-adrenoceptors may modulate neurotransmitter release.

摘要

用间接拟交感神经药酪胺（100微摩尔）灌注输精管可释放三磷酸腺苷（ATP）以及[3H] - 去甲肾上腺素（[3H] - NA）；这一结果与交感神经共同传递的概念相符。2. 虽然酪胺在大鼠输精管中产生强烈收缩，但在豚鼠输精管中几乎没有机械作用。这似乎主要是因为与大鼠相比，酪胺从豚鼠输精管诱导释放的ATP和NA水平要低得多。此外，酪胺释放的NA似乎能从大鼠输精管的次级池中释放ATP，但豚鼠的输精管则不然，因为哌唑嗪可减少酪胺诱导的大鼠输精管中ATP的释放。3. α,β - 亚甲基ATP（α,β - meATP）增加了ATP的自发释放以及酪胺诱发的ATP和[3H] - NA流出。α1 - 肾上腺素能受体拮抗剂哌唑嗪也增强了[3H] - NA的基础流出和酪胺诱导的流出，这表明突触前α1 - 肾上腺素能受体可能调节神经递质的释放。