Tityustoxin K alpha blocks voltage-gated noninactivating K+ channels and unblocks inactivating K+ channels blocked by alpha-dendrotoxin in synaptosomes.
نویسندگان
چکیده
منابع مشابه
Inactivation of voltage-gated cardiac K+ channels.
Inactivation is the process by which an open channel enters a stable nonconducting conformation after a depolarizing change in membrane potential. Inactivation is a widespread property of many different types of voltage-gated ion channels. Recent advances in the molecular biology of K+ channels have elucidated two mechanistically distinct types of inactivation, N-type and C-type. N-type inactiv...
متن کاملNovel activation of voltage-gated K(+) channels by sevoflurane.
BACKGROUND Halogenated inhaled anesthetics modulate voltage-gated ion channels by unknown mechanisms. RESULTS Biophysical analyses revealed novel activation of K(v) channels by the inhaled anesthetic sevoflurane. CONCLUSION K(v) channel activation by sevoflurane results from the positive allosteric modulation of activation gating. SIGNIFICANCE The unique activation of K(v) channels by sev...
متن کاملThe Origin of Subconductance Levels in Voltage-gated K+ Channels
Typical single channel recordings in voltage-dependent K channels show two simple conductance states: open or shut. Considering the fact that K channels are assembled with four identical subunits, the classical interpretation has been that the conduction pathway is not formed unless all four subunits are in their active positions. In fact, this agrees with the molecular interpretation of the op...
متن کاملCharybdotoxin blocks voltage-gated K+ channels in human and murine T lymphocytes
A variety of scorpion venoms and purified toxins were tested for effects on ion channels in human T lymphocytes, a human T leukemia cell line (Jurkat), and murine thymocytes, using the whole-cell patch-clamp method. Nanomolar concentrations of charbdotoxin (CTX), a purified peptide component of Leiurus quinquestriatus venom known to block Ca2+-activated K+ channels from muscle, blocked "type n"...
متن کاملTaking Apart the Gating of Voltage-Gated K+ Channels
؉ Channels labeling studies of KcsA suggest that K ϩ channels may gate by rotating the inner helices that line the pore (Per-ozo et al., 1999). In this model, the degree of rotation of the helices regulates the aperture of the inner mouth of the pore that opens and closes like the shutters of a San Francisco, California 94143 camera. For voltage-gated K ϩ channels, this model is broadly consist...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Proceedings of the National Academy of Sciences
سال: 1994
ISSN: 0027-8424,1091-6490
DOI: 10.1073/pnas.91.4.1475