Davis P B, Byard P J
Department of Pediatrics, Case Western Reserve University School of Medicine, Rainbow Babies and Children's Hospital, Cleveland, OH.
Mech Ageing Dev. 1990 May 15;54(1):29-42. doi: 10.1016/0047-6374(90)90013-6.
Healthy adults aged 18-90 years were tested for lymphocyte and granulocyte cyclic AMP responses to isoproterenol and prostaglandin E1 (PGE1), beta-adrenergic receptor density and antagonist binding properties, and for airway reactivity to methacholine. Our hypothesis was that reduced beta-adrenergic responses occur with aging and are associated with increased airway reactivity. This hypothesis was not supported by the data. Lymphocyte stimulation ratios (cyclic AMP level with stimulation/baseline cyclic AMP level) at higher concentrations of isoproterenol and PGE1 increased significantly with age. There were no significant age trends for any of the other variables. None of the beta-adrenergic responses or receptor properties correlated with airway reactivity to methacholine. beta-Adrenergic responses in lymphocytes and granulocytes from the same subject were weakly correlated at high concentrations. Prior studies which suggest that reduced beta-adrenergic responses and increased airway reactivity are concomitants of normal aging may differ from the present study in subject selection. In healthy older subjects, there appears to be no reduction in leukocyte beta-adrenergic responses or receptor properties and no change in airway reactivity.
对18至90岁的健康成年人进行了检测，以观察淋巴细胞和粒细胞对异丙肾上腺素和前列腺素E1（PGE1）的环磷酸腺苷（cAMP）反应、β-肾上腺素能受体密度和拮抗剂结合特性，以及对乙酰甲胆碱的气道反应性。我们的假设是，β-肾上腺素能反应随年龄增长而降低，并与气道反应性增加有关。但数据并不支持这一假设。在较高浓度的异丙肾上腺素和PGE1作用下，淋巴细胞刺激率（刺激时的环磷酸腺苷水平/基线环磷酸腺苷水平）随年龄显著增加。其他任何变量均无显著的年龄趋势。β-肾上腺素能反应或受体特性与对乙酰甲胆碱的气道反应性均无相关性。同一受试者的淋巴细胞和粒细胞中的β-肾上腺素能反应在高浓度时呈弱相关。先前的研究表明，β-肾上腺素能反应降低和气道反应性增加是正常衰老的伴随现象，这些研究在受试者选择方面可能与本研究不同。在健康的老年受试者中，白细胞的β-肾上腺素能反应或受体特性似乎没有降低，气道反应性也没有变化。
