A newly developed local anesthetic blocks $\mathrm{Na}^{+}$channels in nerves. Which of the following effects on the action potential would it be expected to produce?

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[IV E 1-3]. Blockade of the $\mathrm{Na}^{+}$channels would prevent action potentials. The upstroke of the action potential depends on the entry of $\mathrm{Na}^{+}$into the cell through these channels and therefore would also be reduced or abolished. The absolute refractory period would be lengthened because it is based on the availability of the $\mathrm{Na}^{+}$channels. The hyperpolarizing afterpotential is related to increased $\mathrm{K}^{+}$permeability. The $\mathrm{Na}^{+}$equilibrium potential is calculated from the Nernst equation and is the theoretical potential at electrochemical equilibrium (and does not depend on whether the $\mathrm{Na}^{+}$channels are open or closed).

A Newly Developed Local Anesthetic Blocks Na+\mathrm{Na}^{+}Na+ Channels in Nerves Na+\mathrm{Na}^{+}Na+ Equilibrium Potential E) Decrease The

A Newly Developed Local Anesthetic Blocks $\mathrm{Na}^{+}$ Channels in Nerves $\mathrm{Na}^{+}$ Equilibrium Potential
E) Decrease The