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Updated: Aug 16, 2026

Optical Mapping of Intra-Sarcoplasmic Reticulum Ca2+ and Transmembrane Potential in the Langendorff-perfused Rabbit Heart
Published on: September 10, 2015
[Binding of GTP and GTPase activity of rabbit myocardial sarcolemma]
Abstract:
Binding [3H] GTP and GTP-ase activity were studied on the isolated preparation of myocardium sarcolemma. The Muscarinic acetylcholine receptors against carbocholine (10(-4) M) was shown to stimulate both the GTP binding by sarcolemma and its GTP-ase activity. The activating effect of carbocholine is blocked by the Muscarinic acetylcholine receptors antagonist atropine (10(-6) M). The GTP-ase activity of sarcolemma is reduced in presence of sodium fluoride which points out the enzyme activity of G-proteins. Thus, functioning of G-proteins and their Muscarinic acetylcholine receptors regulation were showed during in vitro experiments on preparation of myocardium sarcolemma.
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