RESUMEN
We studied the effects of BgK toxin on outward K(+) currents in isolated neurons of the snail Helix aspersa, using the whole cell patch clamp technique. BgK partially and reversibly blocked K(+) currents in the 1 pM to 100 nM concentration range (n=53). The dose-response curve for BgK current inhibition had a maximum blocking effect at 100 nM. Our results indicate that BgK is a potent, apparently non-selective, K(+) channel blocker in molluscan neurons.
Asunto(s)
Venenos de Cnidarios/farmacología , Neuronas/química , Neuronas/fisiología , Bloqueadores de los Canales de Potasio , Animales , Relación Dosis-Respuesta a Droga , Caracoles Helix , Potenciales de la Membrana/efectos de los fármacos , Técnicas de Placa-Clamp , Potasio/metabolismo , Canales de Potasio/fisiología , Anémonas de MarRESUMEN
A program for action potential waveform analysis based on a PC compatible computer is described. Single or averaged action potentials are analyzed by obtaining its first derivative and using criteria which allow automatic measurement of several action potential components, including: depolarization rate, repolarization rate, amplitude, duration, resting membrane potential and afterhyperpolarization amplitude and slope. Data can be imported from pClamp (Axon Instruments) and exported to other software such as Excel, Sigmaplot and MatLab for example.