A novel agonist, phorbol 12-phenylacetate 13-acetate 20-homovanillate, abolishes positive cooperativity of binding by the vanilloid receptor
作者:Arpad Szallasi、Geza Acs、Giancarlo Cravotto、Peter M. Blumberg、Jan M. Lundberg、Giovanni Appendino
DOI:10.1016/0014-2999(95)00864-0
日期:1996.3
capsazepine. Upon binding to its receptor, capsaicin opens a cation channel leading to Ca2+ influx. The binding of capsaicin or resiniferatoxin by the vanilloid receptor follows a sigmoidal saturation curve, indicative of positive cooperativity. The biological significance of this positive cooperative behaviour is unknown, as is the mechanism responsible for it. We have developed a novel ligand, phorbol
辣椒素与特定的识别位点结合,称为香草素受体,与天然的超强效激动剂resiniferatoxin和竞争性拮抗剂辣椒素共有。辣椒素与其受体结合后,打开一个阳离子通道,导致Ca2 +大量涌入。辣椒素受体与辣椒素或树脂毒素的结合遵循S形饱和曲线,表明正协同性。这种积极的合作行为的生物学意义以及导致这种行为的机制尚不清楚。我们已经开发出一种新型配体,佛波醇12-苯基乙酸13-乙酸20-异戊酸酯(PPAHV),它与培养的大鼠感觉神经元(Ki为3.1 +/- 0.4 microM)结合,并诱导它们吸收Ca2 +( ED50为1.8 +/- 0。3 microM)具有相似的亲和力并且以非合作方式进行(结合和Ca2 +吸收的希尔系数分别为0.99和1.06)。PPAHV的行为因此与树脂毒素或辣椒素形成对比,不仅缺乏协同性,而且树脂脂毒素结合与Ca2 +吸收的相对效力也有所不同(树脂毒素毒素的效力较弱,而辣椒素对Ca2