细胞外钠离子置换及D - 600对完整鸽红细胞中肾上腺素激活腺苷酸环化酶的影响。

Effect of replacement of extracellular sodium ions and of D-600 on the activation by adrenalin of adenylate cyclase in intact pigeon erythrocytes.

作者信息

Campbell A K, Siddle K

出版信息

Mol Cell Endocrinol. 1978 Jun;11(1):79-89. doi: 10.1016/0303-7207(78)90034-5.

Abstract

The effect of replacement of extracellular Na+ by Li+, choline K+ or sucrose on cyclic AMP formation in pigeon erythrocytes has been investigated. Replacement of extracellular Na+ by Li+, choline or sucrose but not by K+ inhibited the stimulation by adrenalin of cyclic AMP formation, but had no detectable effect on cyclic AMP content in the absence of adrenalin. This inhibition was observed in the presence or absence of extracellular Ca2+. The relative inhibition caused by Na+ removal decreased with increasing adrenalin concentration. It was concluded that extracellular Na+ or K+ ions were required for maximal activation of adenylate cyclase by low concentrations of adrenalin, and that this effect of monovalent cations may have been due to an effect on the affinity of the receptor for adrenalin. The verapamil derivative D-600 also inhibited the stimulation by adrenalin of cyclic AMP formation. This effect occurred in the absence of extracellular Ca2+ and hence seemed to be unrelated to the inhibition by C-600 of the slow Ca2+ channel in electrically excitable tissues.

摘要

研究了用Li⁺、胆碱、K⁺或蔗糖替代细胞外Na⁺对鸽红细胞中环状AMP形成的影响。用Li⁺、胆碱或蔗糖而非K⁺替代细胞外Na⁺可抑制肾上腺素对环状AMP形成的刺激作用，但在无肾上腺素时对环状AMP含量无明显影响。无论有无细胞外Ca²⁺，均观察到这种抑制作用。随着肾上腺素浓度的增加，因去除Na⁺引起的相对抑制作用减弱。得出的结论是，低浓度肾上腺素使腺苷酸环化酶最大程度激活需要细胞外Na⁺或K⁺离子，单价阳离子的这种作用可能是由于对肾上腺素受体亲和力的影响。维拉帕米衍生物D - 600也抑制肾上腺素对环状AMP形成的刺激作用。这种作用在无细胞外Ca²⁺时出现，因此似乎与D - 600对可兴奋组织中慢Ca²⁺通道的抑制作用无关。