Neurotoxin Effects Of Roth 801, A Aental Sealer, On The Spontaneousbioelectrical Activity Of F1 Neuronal Cells In Helix Aspersa: Using Current-Clamp Technique

Document Type : Original Article


Physiology Department ,shaheed Beheshti Sciences University,Tehran .Iran


Introduction: Some dental sealers have neurotoxic effects on neuronaltissues. These effects appear to be mediated through the inhibition of ionic channels. Intracellular recording was performed on neuronal cells tocharacterize the underlying ionic mechanisms of neurotoxicity induced by Roth 801.
Materials and Methods: Experiments were carried out on F1 neuronal soma membrane located in the right parietal ganglion of snail, Helix aspersa. The properties of action potential were analyzed using singl eelectrode current clamp method. Roth 801 was applied to the bathing solution in invasive and gradual forms.
Results: In the current clamp experiments, several parameters, including, resting membrane potential (RMP), the peak amplitude of action potential, spike width, frequency, the peak amplitude of after hyperpolarization (AHP) were analyzed. In both invasive and gradual forms Roth 801 decreased the peak of amplitude and frequency of action potential and the peak amplitude of AHP. But the duration of spike was prolonged. After invasive application of Roth 801, membrane potential was depolarized. However in gradual method, it was initially hyperpolarized and subsequently shifted towards depolarized potential.
Conclusion: These results suggest that Roth 801 affects shape and frequency of action potential through inhibition of ionic currents.