akram aboutorabi

Bothutous Schach (BS) scorpion venom consists of several polypeptides that could modulate ion channels. In this study, the effects of BS crude venom on passive and active electrophysiological properties of rat neurons in supraoptic nucleus (SON) of hypothalamus was investigated using whole-cell patch clamp technique. The results showed that bath application of BS venom produced significant change in passive properties of SON neurons, namely a decrease in resting membrane potential and an increase in input resistance of the cells. Also, significant change in active properties of SON neurons was shown after bath application of BS venom; including a decrease in the number of evoked action potential along with an increase in half width and decay time of action potential and a significant decrease in afterhyperpolarization amplitude. Finally, a decreased latency to the first spike accompanied by a lower current threshold to elicit the first spike was shown compared with the values before venom application. These effects are possibly through blocking different ion channels including potassium channels. Further experiments using different fractions of the venom is required to specify venom effects on various ion channels.

Buthotus schach is one of the dangers scorpion in Iran that belong to the Buthidae family. Toxins are existing in venom scorpion, modulate the ion channels by blocking or opening the pore of the channel or by altering the voltage gating and useful as pharmacological tools. In the present study, we investigated the effect of venom and its obtained fractions by gel filtrations on electrophysiological properties of magnocellular supraoptic of hypothalamus by using whole cell patch clamp. In our result were shown, scorpion crude venom and its fraction effect on Na gated voltage channels. A significant decrease was revealed in amplitude firing, in venom various concentration and some of the venom fraction. Also a significant increase was shown in half width and rise time 10% to 90% actions potential firing. Previous evidence was revealed change in electrophysiological properties such as amplitude and rise time 10% to 90%, related to sodium gated voltage channels. Sodium channels toxins existed on scorpion venom caused modulate on sodium channels. In order to access bioactive components, six fractions were collected by gel chromatography techniques. After bath application of fraction, four components were found F2, F3, F4 and F6. Also F2 and F3 component show the same effects than venom on electrophysiological properties of magnocellular supraoptic than venom.