High affinity binding of [125I]monoiodoapamin to isolated guinea‐pig hepatocytes
- 21 February 1983
- journal article
- Published by Wiley in FEBS Letters
- Vol. 152 (2) , 265-269
- https://doi.org/10.1016/0014-5793(83)80393-7
Abstract
The bee venom neurotoxin apamin has been labelled with 125I and its binding to isolated guinea-pig hepatocytes measured under physiological conditions. A single saturable component of [125I]monoiodoapamin binding with a K d of 350 pM and B max of 0.99 fmol/mg dry wt was identified. Native apamin displaced labelled apamin with a K d of 376 pM which is broadly in keeping with the concentrations found to inhibit K loss from guinea-pig hepatocytes. These observations, together with the binding found in other tissues, suggest that specific binding of labelled apamin is particularly associated with apamin-sensitive, Ca-activated K-channels.Keywords
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