Henson P M, Gould D, Becker E L
J Exp Med. 1976 Dec 1;144(6):1657-73. doi: 10.1084/jem.144.6.1657.
The effect of organophosphorus inhibitors of serine esterases (proteases) on secretion from washed rabbit platelets was examined. Five noncytotoxic stimuli were employed: collagen, thrombin, heterologous anti-platelet antibody (in the absence of complement), rabbit C3 bound to zymosan, and platelet activating factor derived from antigen-stimulated, IgE-sensitized rabbit basophils. Diisoprophyl phosphofluoridate, three series of p-nitrophenyl ethyl phosphonates, and a series of cyclohexyl phenylalkylphosphonofluridates were all found to be inhibitory to the platelet secretion. These are irreversible inhibitors of serine proteases but in this system were only inhibitory if added to the platelets concurrently with the stimuli. Pretreatment of either the platelets or the stimuli with the inhibitors followed by washing, was without effect on the subsequent reaction. This suggested the involvement of stimulus-activatable serine proteases in the secretory process. The concept was supported by finding that nonphosphorylating phosphonates or hydrolyzed phosphonates or phosphonofluoridates were without inhibitory action. The effect of a series of phosphonates or phosphonoflouridates in inhibiting each stimulus exhibited a unique activity-structure profile. The demonstration of such unique profiles with four series of inhibitors for each of the five stimuli was interpreted as demonstrating that a specific activatable serine protease was involved in the platelet secretory response to each stimulus.
研究了丝氨酸酯酶（蛋白酶）的有机磷抑制剂对洗涤过的兔血小板分泌的影响。采用了五种无细胞毒性的刺激物：胶原蛋白、凝血酶、异源抗血小板抗体（无补体存在时）、结合酵母聚糖的兔C3以及源自抗原刺激的、IgE致敏的兔嗜碱性粒细胞的血小板活化因子。发现二异丙基磷氟化物、三个系列的对硝基苯基乙基膦酸酯以及一系列环己基苯基烷基膦酰氟化物均对血小板分泌有抑制作用。这些是丝氨酸蛋白酶的不可逆抑制剂，但在该系统中，只有在与刺激物同时添加到血小板中时才具有抑制作用。用抑制剂对血小板或刺激物进行预处理后洗涤，对随后的反应没有影响。这表明刺激可激活的丝氨酸蛋白酶参与了分泌过程。这一概念得到了以下发现的支持：非磷酸化膦酸酯或水解膦酸酯或膦酰氟化物没有抑制作用。一系列膦酸酯或膦酰氟化物对每种刺激的抑制作用呈现出独特的活性-结构特征。用针对五种刺激物中的每一种的四个系列抑制剂证明了这种独特的特征，这被解释为表明一种特定的可激活丝氨酸蛋白酶参与了血小板对每种刺激的分泌反应。
