O'Donnell J P, Hogaboom G K, Fedan J S
Eur J Pharmacol. 1983 Jan 21;86(3-4):435-40. doi: 10.1016/0014-2999(83)90193-0.
Two chemically related arylazido photoaffinity analogs of ATP (arylazido aminopropionyl ATP (ANAPP3) and arylazido aminobutyryl ATP (ANABP3)), which have been reported in the literature to differ in their ability to inhibit myosin ATPase, were compared for their ability to antagonize contractile responses of the isolated guinea-pig vas deferens to ATP. During photolysis in organ chambers the photoconversion (delta A260/delta t) of ANAPP3 occurred with greater than first order kinetics or was multiexponential and t1/2 = 7.5 min, while delta A260/delta t for ANABP3 was first order and t1/2 = 2.25 min. After photolysis of these compounds in the presence of the guinea-pig vas deferens, using irradiation periods which caused 80% consumption of the compounds, ANABP3 was 2-3 times more potent than ANAPP3 in antagonizing contractions to ATP, which are mediated by P2-purinergic receptors. A comparison of concentration-response curves obtained for nonphotolyzed ANAPP3 and ANABP3 used as agonists suggested that the greater antagonism produced by photolyzed ANABP3 is not attributable to a greater potency. The results suggest that the longer 3'-hydroxyl-arylazide bridge length of ANABP3 places the arylnitrene intermediate in a position at or near the P2-receptor which is more favorable for covalent insertion.
文献报道过两种化学相关的ATP芳基叠氮光亲和类似物（芳基叠氮氨基丙酰ATP（ANAPP3）和芳基叠氮氨基丁酰ATP（ANABP3）），它们抑制肌球蛋白ATP酶的能力不同，本文比较了它们拮抗豚鼠离体输精管对ATP收缩反应的能力。在器官浴槽中光照期间，ANAPP3的光转化（ΔA260/Δt）呈现大于一级的动力学或为多指数形式，t1/2 = 7.5分钟，而ANABP3的ΔA260/Δt为一级动力学，t1/2 = 2.25分钟。在豚鼠输精管存在的情况下对这些化合物进行光照，使用能使化合物消耗80%的光照时间，在拮抗由P2嘌呤能受体介导的对ATP的收缩反应方面，ANABP3的效力是ANAPP3的2 - 3倍。对用作激动剂的未光照ANAPP3和ANABP3所获得的浓度 - 反应曲线进行比较表明，光照后的ANABP3产生的更大拮抗作用并非归因于更强的效力。结果表明，ANABP3中更长的3'-羟基 - 芳基叠氮桥长度使芳基氮烯中间体处于P2受体处或其附近的一个更有利于共价插入的位置。
