Abstract
Effects of G protein βγ subunits from rat brain on cardiac K+ channel was examined in single atrial cells of guinea-pig, using patch clamp techniques. We found that 10 pM concentration of rat brain βγ subunits preparation could activate the atrial muscarine receptor-gated K+ channel (IK.ACh). Neither the detergent, CHAPS, used to suspend βγ nor the boiled βγ preparation activated IK.ACh. Furthermore, preincubation of βγ subunits preparation in Mg2+-free solution, which easily inactivated α-GTP-γS, did not affect βγ-activation of IK.ACh. We concluded, therefore, that βγ subunits themselves can activate IK.ACh.
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Supported by the grants from the Ministry of Education, Culture and Science of Japan and from the Calcium Signal Workshop on Cardiovascular Systems
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Kurachi, Y., Ito, H., Sugimoto, T. et al. Activation of atrial muscarinic K+ channels by low concentrations ofβγ subunits of rat brain G protein. Pflugers Arch. 413, 325–327 (1989). https://doi.org/10.1007/BF00583550
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DOI: https://doi.org/10.1007/BF00583550