Biddulph D M, Wrenn R W
J Cyclic Nucleotide Res. 1977 Apr;3(2):129-38.
The effects of parathyroid hormone (PTH) on concentrations of cyclic AMP and cyclic GMP were investigated in isolated renal cortical tubules from hamsters. Efflux of 45Ca from tubules was compared to temporal changes in both cyclic nucleotide concentrations. A rapid increase in cyclic AMP occurred following addition of PTH which was maximal by 1 min but decreased over the next 4 min period. Cyclic GMP concentrations were not significantly altered at 1 min but increased between 1 and 5 min from basal levels. Concentrations of both nucleotides remained significantly elevated from basal levels between 5 and 15 min following PTH. Efflux of 45Ca was increased by PTH with time-course changes closely paralleling changes in cyclic GMP concentrations. Changes in both cyclic AMP and cyclic GMP were related to PTH concentrations of the incubation media and were increased by addition of theophylline. Increasing the calcium concentration from 1 to 3 mM did not significantly alter the effect of PTH on cyclic AMP, however, cyclic GMP concentrations were further increased.
研究了甲状旁腺激素（PTH）对仓鼠离体肾皮质小管中环磷酸腺苷（cAMP）和环磷酸鸟苷（cGMP）浓度的影响。将小管中45Ca的流出与两种环核苷酸浓度的时间变化进行了比较。添加PTH后，cAMP迅速增加，1分钟时达到最大值，但在接下来的4分钟内下降。cGMP浓度在1分钟时无显著变化，但在1至5分钟内从基础水平升高。PTH作用后5至15分钟，两种核苷酸的浓度均显著高于基础水平。PTH使45Ca的流出增加，其时间进程变化与cGMP浓度变化密切平行。cAMP和cGMP的变化均与孵育介质中的PTH浓度有关，并因添加茶碱而增加。将钙浓度从1 mM提高到3 mM并未显著改变PTH对cAMP的作用，然而，cGMP浓度进一步升高。
