Selectivity of omega-CgTx-MVIIC toxin from Conus magus on calcium currents in enteric neurons. |
| |
| Authors: | A M Starodub J D Wood |
| |
| Institution: | Department of Physiology, College of Medicine, The Ohio State University, Columbus 43210-1218, USA. |
| |
| Abstract: | Whole-cell perforated patch clamp recordings were used to analyze selectivity of omega-CgTx-MVIIC toxin for voltage-dependent calcium currents in cultured myenteric neurons from guinea-pig small intestine. Omega-CgTx-MVIIC (300 nM) blocked 37 +/- 9% of the peak current activated from -80 mV in 15 neurons by mostly affecting the plateau phase of the current. The toxin suppressed peak current activated from -30 mV dose-dependently with an IC50 of 70 +/- 8 nM. The blockade was complete at toxin concentrations of 1 microM. Thus, it appears that omega-CgTx-MVIIC blocks high voltage activated (HVA) calcium channels in the myenteric neurons unselectively as well as other types of HVA Ca2+ channels including P and Q channels. |
| |
| Keywords: | |
|
|
