Spontaneous release of GDP from Gi proteins and inhibition of adenylyl cyclase in cardiac sarcolemmal membranes

@article{Lutz2001SpontaneousRO,
  title={Spontaneous release of GDP from Gi proteins and inhibition of adenylyl cyclase in cardiac sarcolemmal membranes},
  author={Susanne Lutz and Doris Baltus and Karl Heinz Jakobs and Feraydoon Niroomand},
  journal={Naunyn-Schmiedeberg's Archives of Pharmacology},
  year={2001},
  volume={365},
  pages={50-55}
}
Several studies have shown an activation of adenylyl cyclase by the G protein-inactivating guanine nucleotides, GDP and its phosphate transfer-resistant analog, guanosine 5'-O-(2-thiodiphosphate; GDPβS). Here, we studied the mechanism underlying this unconventional activation. Adenylyl cyclase activity in sarcolemmal membranes from failing human ventricular myocardium, at a low Mg2+ concentration, decreased rapidly during incubation at 37°C. This decrease in enzyme activity was paralleled by a… CONTINUE READING