Naumov A P, Kuryshev Y A, Kaznacheyeva E V, Mozhayeva G N
Institute of Cytology of Russian Academy of Sciences, St. Petersburg.
FEBS Lett. 1992 Nov 30;313(3):285-7. doi: 10.1016/0014-5793(92)81210-d.
The patch-clamp technique was used to study mechanisms of ATP-induced Ca2+ influx in rat peritoneal macrophages. The experiments on whole-cell and patch membranes have shown that extracellular ATP activates channels permeable to di- and monovalent inorganic cations. Ratios of unitary channel conductances in 105 mM Ca2+, Sr2+, Mn2+, Ba2+ and normal sodium solutions were 1.0, 0.95, 0.75, 0.55 and 0.85, respectively. The channels could open in the presence of non-hydrolyzable GTP analogues in artificial intracellular solution. The data are consistent with the hypothesis that a GTP-binding protein is involved in receptor-to-channel coupling.
