来自牛神经垂体的神经分泌颗粒膜中腺苷酸环化酶活性的证据。

Evidence for an adenylate-cyclase activity in neurosecretory granule membranes from bovine neurohypophysis.

作者信息

Bonne D, Nicolas P, Lauber M, Camier M, Tixier-vidal A, Cohen P

出版信息

Eur J Biochem. 1977 Sep;78(2):337-42. doi: 10.1111/j.1432-1033.1977.tb11745.x.

DOI:10.1111/j.1432-1033.1977.tb11745.x

Abstract

Purified bovine neurosecretory granules and their corresponding membranes were prepared after fractionation and purification processes from bovine pituitaries. An adenylate cyclase activity was detected both in the granules (apparent Km = 0.5 mM) and the corresponding preparations of the membranes (apparent Km = 0.5 mM). This enzyme was activated by fluoride in a way markedly dependent on the concentration of this ion, and with a maximum for a concentration of F- = 3.5 mM. The cyclase activity was also significantly enhanced by GTP. The reaction rate showed a strong dependence on the molar ration [Mg2+]/[ATP] with maximal velocity for 7. It is suggested that this activity might play an important role in the control and regulation of neurosecretion in the neurohypophysis.

摘要

从牛垂体经分级分离和纯化过程制备了纯化的牛神经分泌颗粒及其相应的膜。在颗粒（表观Km = 0.5 mM）和相应的膜制剂（表观Km = 0.5 mM）中均检测到腺苷酸环化酶活性。该酶被氟化物激活，其激活方式明显依赖于该离子的浓度，在F-浓度为3.5 mM时达到最大值。GTP也显著增强了环化酶活性。反应速率对摩尔比[Mg2+]/[ATP]有很强的依赖性，在[Mg2+]/[ATP]为7时达到最大速度。提示该活性可能在神经垂体神经分泌的控制和调节中起重要作用。