Dynamic regulation of leukocyte beta adrenergic receptor-agonist interactions by physiological changes in circulating catecholamines.
Dynamic regulation of leukocyte beta adrenergic receptor-agonist interactions by physiological changes in circulating catecholamines.
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通过循环儿茶酚胺的生理变化动态调节白细胞β肾上腺素能受体激动剂相互作用。
DOI：
10.1172/jci110954
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发表时间：
1983
期刊：
影响因子：
--
通讯作者：
Wood,AJ
中科院分区：
文献类型：
--
作者：
Feldman,RD;Limbird,LE;Nadeau,J;FitzGerald,GA;Robertson,D;Wood,AJ
使用[125 I]碘羟苄基吲哚洛尔结合评估人单核白细胞上的β-肾上腺素能受体。受试者在仰卧和走动后进行研究，这一动作使血浆儿茶酚胺增加约两倍。通过（-）异丙肾上腺素与[125 I]碘羟苄基吲哚洛尔结合的竞争性测定，激动剂的β受体亲和力在使用安替洛尔时显著降低，这种降低与β受体结合激动剂的比例从平均（+/- SEM）42 +/- 5降低至24 +/- 2%（P <0.01）相关。在一个平行的系列中，β-肾上腺素能刺激的腺苷酸环化酶活性也随着姿势的改变而降低，从4.6 +/- 1.1到2.4 +/- 0.6 pmol [32 P]cAMP/min/mg蛋白（P <0.05）。在输注去甲肾上腺素后，观察到具有高亲和力的受体结合激动剂的比例类似降低。我们的结论是，ampletin的机动性降低白细胞β-受体的反应性和亲和力的激动剂，可能是通过增加血浆儿茶酚胺介导的β-受体-腺苷酸环化酶复合物的解偶联的效果。
beta-Adrenergic receptors on human mononuclear leukocytes were assessed using [125I]iodohydroxybenzylpindolol binding. Subjects were studied supine and after being ambulatory, a maneuver that increases plasma catecholamines approximately two-fold. beta-Receptor affinity for agonists, measured by the competition of [125I]iodohydroxybenzylpindolol binding by (-)isoproterenol was significantly reduced with ambulation and this reduction was associated with a reduction in the proportion of beta-receptors binding agonist with a high affinity from a mean (+/- SEM) of 42 +/- 5 to 24 +/- 2% (P less than 0.01). In a parallel series, beta-adrenergic-stimulated adenylate cyclase activity was also reduced with postural change from 4.6 +/- 1.1 to 2.4 +/- 0.6 pmol [32P]cAMP/min per mg protein (P less than 0.05) after ambulation. Similar reductions in the proportion of receptors binding agonist with a high affinity were seen after infusion of norepinephrine. We conclude that the maneuver of ambulation reduces leukocyte beta-receptor responsiveness and affinity for agonists, probably by the effect of increased plasma catecholamines mediating an uncoupling of the beta-receptor-adenylate cyclase complex.