Albert, the patient in question 3, takes the drug lithium, which reduces the permeability of the neuronal axolemma to Na+ (that is, it allows fewer Na+ to enter the axon). Predict the effect this would normally have on his neuronal action potentials. Do you think this drug would be beneficial or harmful, considering his condition?

Video transcript

Hey, everyone. Let's take a look at this question. Together the drug lithium lowers the accessibility of sodium into the neuronal axon. Explain how this would affect action potentials. Is it answer choice? A generation of action potentials will be slowed. Answer choice B action potentials across the membrane will be accelerated. Answer choice C the action potential generated by the neuron will be stronger or answer choice D none of the above. Let's work this problem out together to try to figure out which of the following answer choices best explains how the drug lithium which lowers the accessibility of sodium into the neuronal axon would affect action potentials. So in order to solve this question, we have to recall, we have learned about how sodium moving into the neuronal axon affects action potentials to determine how that lower accessibility of the sodium would affect those action potentials. And we can recall that these sodium ions help with the depolarization of the membrane for action potentials. Since the sodium ions which are positive ions help de increase the polarity of the membrane or depolarize it for the generation of action potentials. So a lack of sodium ions would result in slower depolarization, which in turn results in less action potential generation. So looking at our answer choices, we can see answer choice A which says that the generation of action potentials will be slowed as a result of that lower accessibility of sodium ions into the neuronal axon, which is the correct answer and all other answer choices are incorrect. Since answer choice B and C would be the result of a greater accessibility of sodium ions into the neuronal axon. So answer choice A is the only correct answer choice. I hope you found this video to be helpful. Thank you and goodbye.