Binding of 2-azidoadenosine [beta-32P]diphosphate to the receptor on intact human blood platelets which inhibits adenylate cyclase.
Binding of 2-azidoadenosine [beta-32P]diphosphate to the receptor on intact human blood platelets which inhibits adenylate cyclase.
复制标题
2-叠氮腺苷 [β-32P]二磷酸与完整人血小板上的受体结合，抑制腺苷酸环化酶。
DOI：
10.1021/bi00532a020
复制
发表时间：
1982
期刊：
影响因子：
2.9
通讯作者：
Srivastava,PC
中科院分区：
文献类型：
--
作者：
Macfarlane,DE;Mills,DC;Srivastava,PC
Donald E. Macfarlane，* 4大卫CB米尔斯和Prem C. Srivastava 8摘要：制备了比活度高达10000 Ci/mol的[/S-32 P]-2-叠氮基-ADP，并用于研究人血小板上的ADP受体。2-叠氮基-ADP作为聚集剂的效力是ADP的约5倍，并且作为前列腺素E]刺激的环AMP在完整血小板中积聚的抑制剂的效力是ADP的10-20倍。2-Azido-ADP在中性pH下以叠氮和四唑的混合物形式存在，低pH有利于叠氮的存在：四唑异构体作为聚集剂和环腺苷酸积累抑制剂的作用比叠氮异构体弱2倍，2-azi-do-ADP的光解产物也弱10-20倍。通过离心技术测得的平衡结合显示，每个血小板约有500个非相互作用的结合位点，其亲和力接近环AMP蓄积的半数最大抑制浓度。结合和解离。二磷酸腺苷（ADP）对血小板有两种不同的作用。它诱导导致聚集的形状变化，并抑制完整血小板的腺苷酸环化酶（米尔斯和麦克法兰，1976）和破碎细胞的腺苷酸环化酶（库珀和罗德贝尔，1979;梅尔维格和雅各布斯，1980）。ADP的这两种作用均被ATP拮抗（Macfarlane &米尔斯，1974）。我们最近发现，完整血小板的腺苷酸环化酶抑制动力学提示与腺苷酸环化酶密切相关的简单受体机制（Macfarlane和米尔斯，1981）。我们还证明巯基络合剂对汞苯磺酸盐阻断ADP对腺苷酸环化酶的抑制作用，但不影响ADP诱导形状改变的能力，这表明血小板上存在两种不同的ADP受体机制（米尔斯和麦克法兰，1977）。当血小板聚集胞内环腺苷酸（cAMP）时，血小板聚集受到抑制，环腺苷酸是由膜结合腺苷酸环化酶合成的。这种酶的作用受前列环素刺激的许多药理学试剂调节（Tateson等人，1977）、PGD 2（米尔斯和麦克法兰（Macfarlane），1976）、PGE、异丙肾上腺素和细胞外腺苷（米尔斯和史密斯，1971）。环磷酸腺苷合成的抑制作用反过来又被α-肾上腺素能药物ADP阻断，
Donald E. Macfarlane,* 4 David CB Mills, and Prem C. Srivastava8 abstract:[/S-32P]-2-Azido-ADP was prepared with a specific activity up to 10000 Ci/mol and used to investigate the ADP receptors on human blood platelets. 2-Azido-ADP was about 5-fold more potent than ADP as an aggregating agent and 10-20-fold more potent as an inhibitor of prostaglandin E] stimulated cyclic AMP accumulation in intact platelets. 2-Azido-ADP exists atneutral pH as a mixture of azide and tetrazole forms, the former being favored by low pH: the tetrazole isomer was 2-fold less potent than the azide isomer both as an aggregating agent and as an inhibitor of cyclic AMP accumulation, and the products of photolysis of 2-azi-do-ADP were also 10-20-fold weaker. Equilibrium binding measured by a centrifugal technique revealed about 500 noninteractive binding sites per platelet with an affinity close to the concentration for half-maximal inhibition of cyclic AMP accumulation. Binding, and dissociation in thepresence of. Adenosine diphosphate (ADP) has two distinguishable effects on blood platelets. It induces the shape change leading to aggregation, and it inhibits the adenylate cyclase of intact platelets (Mills & Macfarlane, 1976) and broken cell prepa-rations (Cooper & Rodbell, 1979; Mellwig & Jakobs, 1980). Both of these effects of ADP are antagonized by ATP (Macfarlane & Mills, 1974). We have recently shown that the kinetics of inhibition of the adenylate cyclase of intact platelets suggest a simple receptor mechanism closely coupled to the adenylate cyclase (Macfarlane & Mills, 1981). We also demonstrated that the thiol complexing agent p-mercuri-benzenesulfonate blocks the inhibition by ADP of the adenylate cyclase but does notaffect ADP’s ability to induce the shape change, suggesting that two different ADP receptor mechanisms exist on platelets (Mills & Macfarlane, 1977). The aggregation of platelets is inhibited when they accu-mulate intracellular cyclic AMP, which is synthesized by the membrane-bound adenylate cyclase. The action of this enzyme is regulated by a number of pharmacological agents, being stimulated by prostacyclin (Tateson et al., 1977), PGD2 (Mills & Macfarlane, 1976), PGE,, isoproterenol, and extracellular adenosine (Mills & Smith, 1971). Thestimulation of cyclic AMP synthesis is in turn blocked by a-adrenergic agents, ADP
登录
查看更多内容
肾上腺素、前列腺素 E1 和鸟嘌呤核苷酸对人血小板腺苷酸环化酶的调节。
影响因子：
4.8
作者：
M. Steer;A. Wood
通讯作者：
A. Wood
2-叠氮腺苷（腺苷的光解类似物）抑制腺苷脱氨酶和血小板聚集
DOI：
--
发表时间：
1976
期刊：
Proceedings of the Royal Society of London. Series B. Biological Sciences
影响因子：
--
作者：
N. Cusack;G. Born
通讯作者：
G. Born
影响血小板中腺苷3:5-环单磷酸积累的药物对血小板聚集的影响。
影响因子：
4.1
作者：
D. C. B. Mills;J. B. Smith
通讯作者：
J. B. Smith
通过 [3H]二氢麦角隐亭结合鉴定人血小板中的 α-肾上腺素能受体
DOI：
--
发表时间：
1978
期刊：
影响因子：
--
作者：
Newman Kd;L. Williams;Bishopric Nh;R. Lefkowitz
通讯作者：
R. Lefkowitz
血小板膜 ADP 结合蛋白的溶解和表征。
影响因子：
4.8
作者：
J. Adler;R. Handin
通讯作者：
R. Handin