Premium
A new class of scorpion toxin binding sites related to an A‐type K + channel: pharmacological characterization and localization in rat brain
Author(s) -
Vacher Hélène,
Romi-Lebrun Régine,
Mourre Christiane,
Lebrun Bruno,
Kourrich Said,
Masméjean Frédérique,
Nakajima Terumi,
Legros Christian,
Crest Marcel,
Bougis Pierre E.,
Martin-Eauclaire Marie-France
Publication year - 2001
Publication title -
febs letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.593
H-Index - 257
eISSN - 1873-3468
pISSN - 0014-5793
DOI - 10.1016/s0014-5793(01)02620-5
Subject(s) - striatum , toxin , cerebellum , venom , hippocampus , binding site , scorpion , chemistry , scorpion venoms , scorpion toxin , biophysics , biology , microbiology and biotechnology , biochemistry , endocrinology , dopamine
A new scorpion toxin (3751.8 Da) was isolated from the Buthus martensi venom, sequenced and chemically synthesized (sBmTX3). The A‐type current of striatum neurons in culture completely disappeared when 1 μM sBmTX3 was applied ( K d =54 nM), whereas the sustained K + current was unaffected. 125 I‐sBmTX3 specifically bound to rat brain synaptosomes (maximum binding=14 fmol mg −1 of protein, K d =0.21 nM). A panel of toxins yet described as specific ligands for K + channels were unable to compete with 125 I‐sBmTX3. A high density of 125 I‐sBmTX3 binding sites was found in the striatum, hippocampus, superior colliculus, and cerebellum in the adult rat brain.