Heath E B, Zull J E
Endocr Res Commun. 1980;7(2):87-98. doi: 10.1080/07435808009065962.
Under conditions designed to reduce non-specific adsorption of parathyroid hormone (PTH), the sensitivity of the renal membrane adenylyl cyclase to PTH was significantly enhanced. Stimulation of the enzyme could be observed at hormone concentrations as low as 2 x 10-11M. In addition, kinetic analysis of hormone activation revealed that under conditions where non-specific adsorption is great, downward concavity of Eadie-Hofstee plots is observed, whereas when such adsorption is reduced these plots become upwardly concave. These results suggest that in the absence of non-specific adsorption, PTH activation of kidney membrane adenylyl cyclase can occur at hormone concentrations approaching physiological. In addition, at low hormone concentrations PTH activation is probably more complex than previously recognized.
在旨在减少甲状旁腺激素（PTH）非特异性吸附的条件下，肾膜腺苷酸环化酶对PTH的敏感性显著增强。在低至2×10⁻¹¹M的激素浓度下即可观察到该酶的刺激作用。此外，对激素激活的动力学分析表明，在非特异性吸附较强的条件下，Eadie-Hofstee图呈向下凹形，而当这种吸附减少时，这些图则变为向上凹形。这些结果表明，在不存在非特异性吸附的情况下，肾膜腺苷酸环化酶的PTH激活可在接近生理水平的激素浓度下发生。此外，在低激素浓度下，PTH激活可能比以前认为的更为复杂。
