Rizzoli R, Bonjour J P
Department of Medicine, University Hospital of Geneva, Switzerland.
J Bone Miner Res. 1988 Dec;3(6):605-9. doi: 10.1002/jbmr.5650030605.
The effect of pertussis toxin, which inactivates the guanine nucleotide binding regulatory proteins Gi and Go on cAMP production in response to parathyroid hormone PGE2 or forskolin, was examined in confluent opossum kidney (OK) cells. This effect was compared with that caused by dexamethasone. The response to PTH was increased in cells preincubated with either agent. The effect of pertussis toxin was selective for PTH, since cAMP production in response to neither PGE2 nor forskolin was increased. In contrast, the response to forskolin was enhanced in dexamethasone-treated cells. These results indicate that both stimulatory and inhibitory guanine nucleotides binding regulatory proteins modulate PTH-induced cAMP production in OK cells. Moreover, pertussis toxin and dexamethasone appear to affect different levels of the PTH-receptor-adenylate cyclase complex.
在汇合的负鼠肾（OK）细胞中，研究了百日咳毒素对环磷酸腺苷（cAMP）产生的影响，该毒素可使鸟嘌呤核苷酸结合调节蛋白Gi和Go失活，从而影响细胞对甲状旁腺激素（PTH）、前列腺素E2（PGE2）或福斯高林的反应。将此效应与地塞米松所引起的效应进行了比较。在用任何一种药物预孵育的细胞中，对PTH的反应均增强。百日咳毒素的效应对PTH具有选择性，因为对PGE2和福斯高林的反应所产生的cAMP均未增加。相反，在地塞米松处理的细胞中，对福斯高林的反应增强。这些结果表明，刺激性和抑制性鸟嘌呤核苷酸结合调节蛋白均调节OK细胞中PTH诱导的cAMP产生。此外，百日咳毒素和地塞米松似乎影响PTH受体 - 腺苷酸环化酶复合物的不同水平。
