Electrophysiological effect of beta-N-methylamino-L-alanine on retzius nerve cells of the leech Haemopis sanguisuga.

We investigated the effect of beta-N-methylamino-L-alanine (L-BMAA) on input membrane resistance of leech Retzius nerve cells and the effect of the same substance on the membrane potential in the presence of 20 mM bicarbonate. Results of our experiments show that L-BMAA significantly reduces input membrane resistance on our model. This leads to the conclusion that L-BMAA depolarizes the cell by increasing membrane permeability and conductance. The effect of L-BMAA in 20 mM bicarbonate is significantly higher than in standard Ringer solution. These results indicate that bicarbonate increases the excitatory effect of L-BMAA in our model.