The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
FTX-3.3 is the proposed structure of a calcium-channel blocking toxin that has been isolated from the funnel web spider (Agelenopsis aperta). The effects of FTX-3.3 and one of its analogues, sFTX-3.3, on acetylcholine release, on presynaptic currents at mouse motor nerve terminals and on whole-cell sodium currents in SK.N.SH cells (a human neuroblastoma cell line) have been studied. FTX-3.3 (10-30...
For many years sea anemones have constituted a source of neuroactive compounds mainly modifying kinetic aspects of sodium channels. In addition, potassium channel blocking activity has been discovered in the aqueous extract of Stichodactyla helianthus and Bunodosoma granulifera (Karlsson et al., 1991), and recently two potassium channel blockers have been isolated: BgK (Aneiros et al., 1993) and...
Previous studies have shown that homologous phospholipases A 2 (PLA 2 ) (Pa-3, Pa-9C, Pa-10F and Pa-11) from the venom of the Australian king brown snake, Pseudechis australis, significantly reduce the resting membrane potentials and quantal contents of endplate potentials recorded from endplate regions of mouse triangularis sterni nerve-muscle preparations. It is not clear whether...
The effect of diamide, a thiol-oxidizing agent, was tested using electrophysiological techniques to determine whether its ability to alter neuromuscular transmission in vitro could be attributed to alterations of ion channels controlling neuronal excitability and/or acetylcholine release. In mouse triangularis sterni preparations, diamide transiently increased the evoked release of acetylcholine...
The effects of the venom of the Sahara sand viper (Cerastes vipera) were studied on isolated chick biventer cervicis, isolated rat atria and vas deferens preparations, and on the electrocardiogram of anaesthetized rats. Effects on 3 H-noradrenaline uptake were studied using rat brain synaptosomes. At 50 μg/ml and 100 μg/ml, the venom caused a transient increase in rate and force of contractions...
Scorpion venoms contain toxins that block different types of potassium channels. Some of these toxins have affinity for high conductance Ca 2+ -activated K + channels and for dendrotoxin-sensitive voltage-dependent K + channels. The structural features that determine the specificity of binding to different channel types are not known. We investigated this using natural...
Ammodytoxin A, the presynaptic neurotoxin from Vipera ammodytes ammodytes venom, was found to bind specifically and with high affinity to bovine cortex synaptic membrane preparation. The detected ammodytoxin A high-affinity binding was characterized by equilibrium binding analysis which revealed a single high-affinity binding site with K d 4.13 nM and B max 6.67 pmoles/mg...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.