Premium
M‐type K + current inhibition by a toxin from the scorpion Buthus eupeus
Author(s) -
Filippov Alexander K.,
Kozlov Sergey A.,
Pluzhnikov Kirill A.,
Grishin Eugene V.,
Brown David A.
Publication year - 1996
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 - 10.1016/0014-5793(96)00333-x
Subject(s) - venom , scorpion , scorpion venoms , chemistry , toxin , scorpion toxin , bradykinin , ic50 , peptide , biochemistry , stereochemistry , receptor , in vitro
A number of invertebrate venoms have been tested for effects on M‐type K + currents ( I K ( M ) ) in differentiated mouse neuroblastoma X rat glioma NG108‐15 cells. Among the venoms tested, Buthus eupeus scorpion venom reversibly inhibited I K ( M ) by ∼ 44% at 50 μg/ml. Inhibition was not due to activation of bradykinin or nucleotide (pyrymidine) receptors. On venom fractionation, a polypeptide of 4 kDa was purified that inhibited I K ( M ) by ∼45% with an IC 50 of ∼;33 nM. Neither the crude venom nor the purified polypeptide affected the Ca 2+ current or the delayed rectifier K + current. While the crude venom prolonged the Na + current, the polypeptide did not. Thus, the 4 kDa Buthus eupeus polypeptide appears to be a selective inhibitor of I K ( M ) in NG108‐15 cells.