Wiklund N P, Samuelson U E, Brundin J
Eur J Pharmacol. 1986 Apr 9;123(1):11-8. doi: 10.1016/0014-2999(86)90681-3.
The effects of adenosine and adenosine analogues on nerve-induced contractile responses and [3H]noradrenaline ([3H]NA) release, were studied in the isthmic part of human oviducts. Adenosine and L-N6-phenylisopropyladenosine (L-PIA) could enhance neurogenic contractile responses in preparations obtained mainly in the proliferative phase. At higher concentrations, adenosine derivatives inhibited contractile responses to nerve stimulation in both proliferative and secretory phase, with the potency order: 5'-N-ethylcarboxamideadenosine (NECA) greater than or equal to L-PIA much greater than D-PIA. This indicated actions at both stimulatory A1- and inhibitory A2-receptors. Adenosine, L-PIA and NECA but not D-PIA inhibited [3H]NA release during nerve stimulation. The relative potency order for the prejunctional inhibition was compatible with an action at A1-receptors. Furthermore, adenosine was found to modulate nerve-induced contractions via postjunctional stimulatory A1- and inhibitory A2-like receptors. The postjunctional effects may be influenced by cyclic hormonal changes. The adenosine antagonist 8-p-sulfophenyltheophylline (PSøT) reversibly antagonized the stimulatory and inhibitory effects by adenosine and analogues.
在人输卵管峡部研究了腺苷及腺苷类似物对神经诱导的收缩反应和[3H]去甲肾上腺素（[3H]NA）释放的影响。腺苷和L-N6-苯异丙基腺苷（L-PIA）可增强主要取自增殖期的标本中的神经源性收缩反应。在较高浓度时，腺苷衍生物在增殖期和分泌期均抑制对神经刺激的收缩反应，其效力顺序为：5'-N-乙基甲酰胺腺苷（NECA）≥L-PIA＞D-PIA。这表明其对刺激性A1受体和抑制性A2受体均有作用。腺苷、L-PIA和NECA可抑制神经刺激期间的[3H]NA释放，但D-PIA无此作用。突触前抑制的相对效力顺序与对A1受体的作用相符。此外，发现腺苷通过突触后刺激性A1受体和抑制性A2样受体调节神经诱导的收缩。突触后效应可能受周期性激素变化的影响。腺苷拮抗剂8-对磺基苯甲酰茶碱（PSøT）可可逆地拮抗腺苷及类似物的刺激和抑制作用。
