Modification of Nifedipine Inhibitory Effect on Calcium Spike and L-Type Calcium Current by Ethanol in F1 Neuron of Helix aspersa
نویسندگان
چکیده
There is strong evidence demonstrating that nifedipine dissolved in ethanol selectively inhibits only Ltype Ca current. In addition, acute ethanol exposure reduces voltage-dependent calcium currents. In the present study, we investigated the antagonistic effect of fixed concentration of nifedipine dissolved in different concentration of ethanol on L-type Ca current. In a Na-K free solution, nifedipine dissolved in 60 and 120 mM ethanol decreased resting membrane potential of Ca spikes and caused a significant reduction in amplitude, duration and an increase in threshold of Ca spikes. Furthermore, Ca current was inhibited by ethanol in a concentration-dependent manner, so that the reduction of L-type Ca current by nifedipine/60 and 120 mM ethanol was statistically significant. Meanwhile, ethanol concentration-dependent response of Ca currents was observed at its late component in more positive potentials. These results may be consistent with ethanol-dependent inhibition of L-type Ca currents and ethanol-dependent enhancment of a Ca-activated potassium current. Iran. Biomed. J. 7
منابع مشابه
Modification of Nifedipine Inhibitory Effect on Calcium Spike and L-Type Calcium Current by Ethanol in F1 Neuron of Helix aspersa
There is strong evidence demonstrating that nifedipine dissolved in ethanol selectively inhibits only L-type Ca2+ current. In addition, acute ethanol exposure reduces voltage-dependent calcium currents. In the present study, we investigated the antagonistic effect of fixed concentration of nifedipine dissolved in different concentration of ethanol on L-type Ca2+ current. In a Na+-K+ free soluti...
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