[Decrease in the maximum sodium permeability and slow sodium inactivation in Ranvier's nodes treated with trimecaine].
The effect of local anesthetic trimecaine on sodium permeability was studied in voltage clamped nerve fibres of the frog. Trimecaine affected PNa by means of two different mechanisms: potential independent block (reduction of PNa) and slow inactivation imposed by prolonged depolarization. Trimecaine induced slow inactivation appeared to be qualitatively similar to that produced by externally applied procaine or high external potassium. According to dose-effect curves one molecule of drug per channel reaction is involved for both mechanisms. The drug molecule has greater affinity for the receptor site responsible for slow inactivation.
Acetanilides↗