Sanders R C, Murray T F
College of Pharmacy, Oregon State University, Corvallis 97331.
Neuropharmacology. 1988 Jul;27(7):757-60. doi: 10.1016/0028-3908(88)90086-x.
Chronic treatment of rats with theophylline (75mg/kg twice-daily for 21 consecutive days) significantly increased the specific binding of [3H]CHA and [3H]DPCPX in cerebral cortical membranes. The absolute increase in the number of binding sites following theophylline treatment was approximately the same for each ligand, although this number represents a larger percentage of the total sites available to [3H]CHA. Saturation analysis of [3H]DPCPX binding indicated that theophylline treatment increased the maximum number of binding sites from 799 +/- 13 to 920 +/- 22 fmol/mg protein, while the affinity of [3H]DPCPX for A1 receptors was unaltered. These results suggest that chronic theophylline exposure produces both an increase in the number of A1 adenosine receptors and an enhancement of coupling of these receptors to G proteins.
用茶碱对大鼠进行长期治疗（75毫克/千克，每日两次，连续21天），可显著增加大脑皮质膜中[3H]CHA和[3H]DPCPX的特异性结合。茶碱治疗后，每种配体结合位点数量的绝对增加量大致相同，尽管该数量在[3H]CHA可利用的总位点中所占百分比更大。[3H]DPCPX结合的饱和分析表明，茶碱治疗使结合位点的最大数量从799±13增加到920±22飞摩尔/毫克蛋白质，而[3H]DPCPX对A1受体的亲和力未改变。这些结果表明，长期接触茶碱会使A1腺苷受体数量增加，且这些受体与G蛋白的偶联增强。
