Wiklund N P, Samuelson U E, Hammarström M
Department of Physiology, Karolinska Hospital, Sweden.
Acta Physiol Scand. 1991 Sep;143(1):33-43. doi: 10.1111/j.1748-1716.1991.tb09199.x.
Effects of adenosine and adenosine analogues on neuroeffector transmission in separate layers of the guinea-pig uterine smooth muscle during different phases of the oestrus cycle were studied. Adenosine (ADO), N6-[(R)-1-methyl-2-phenylethyl]- adenosine (R-PIA) and 5'-N-ethylcarboxamideadenosine (NECA) enhanced spontaneous contractile activity as well as contractile responses to nerve stimulation or direct muscle stimulation in the longitudinal and circular muscle layers both at the time of ovulation and implantation. The agonist potency order was R-PIA greater than or equal to NECA greater than ADO. Furthermore, in the circular muscle layer inhibitory effects were seen at time of implantation and the agonist potency for this inhibitory effect was NECA greater than R-PIA greater than or equal to ADO. 8-p-sulphophenyltheophylline (8-PSOT) antagonized both the stimulatory and inhibitory effects of the purines and 8-p-sulphophenyltheophylline applied to untreated preparations inhibited nerve-induced contractile activity. NECA inhibited stimulation-induced release of 3H in preparations incubated with [3H]noradrenaline. We suggest that adenosine and its analogues can modulate adrenergic neuroeffector transmission in guinea-pig uterine smooth muscle via action at postjunctional receptors stimulating contractile activity and prejunctional receptors inhibiting transmitter release. In the circular muscle layer postjunctional receptors inhibiting contractile activity were evident at time of implantation. Furthermore, endogenous purines exerting a stimulatory action on the neuroeffector transmission were likely formed during the present experimental conditions.
研究了腺苷和腺苷类似物对豚鼠子宫平滑肌不同发情周期阶段各层神经效应传递的影响。腺苷（ADO）、N6-[(R)-1-甲基-2-苯乙基]-腺苷（R-PIA）和5'-N-乙基甲酰胺腺苷（NECA）在排卵和着床时均增强了纵向和环行肌层的自发收缩活动以及对神经刺激或直接肌肉刺激的收缩反应。激动剂效力顺序为R-PIA≥NECA＞ADO。此外，在着床时环行肌层出现抑制作用，且该抑制作用的激动剂效力为NECA＞R-PIA≥ADO。8-对磺基苯甲基黄嘌呤（8-PSOT）拮抗嘌呤的刺激和抑制作用，应用于未处理制剂的8-对磺基苯甲基黄嘌呤抑制神经诱导的收缩活动。NECA抑制与[3H]去甲肾上腺素一起孵育的制剂中刺激诱导的3H释放。我们认为，腺苷及其类似物可通过作用于刺激收缩活动的节后受体和抑制递质释放的节前受体来调节豚鼠子宫平滑肌中的肾上腺素能神经效应传递。在着床时，环行肌层中抑制收缩活动的节后受体很明显。此外，在当前实验条件下可能形成了对神经效应传递发挥刺激作用的内源性嘌呤。
