Cocaine, amphetamine and cathinone, but not nomifensine and pargyline increase calcium inward current in internally perfused neurons.

The influence of cocaine, amphetamine, cathinone, pargyline and nomifensine on inward calcium current was studied using internally perfused neurons of the snail Lymnaea stagnalis. While nomifensine and pargyline inhibited inward calcium current in the concentrations 10(-7)-10(-4) M and did not affect them in the concentrations 10(-9)-10(-8) M, cocaine, amphetamine and cathinone had a biphasic action on inward calcium current, causing activation (10-30 percent) at 10(-9)-10(-7) M, and inhibition at higher concentrations. Only cathinone caused a shift of the I-V characteristics of the membrane along the potential axis.

Influence of taurine on the electrically regulated ionic channels of the somatic membrane of neurons of the pond snail.

The influence of taurine (in concentrations of 10(-8) to 10(-2) mole/liter) on the fast sodium, calcium, and potassium, the slow potassium, and the leakage currents of the somatic membrane of the neurons of the pond snail was investigated. A monotonic decrease was demonstrated in the calcium and the slow potassium currents with an increase in the concentration of taurine. The sodium currents increased at taurine concentrations of 10(-8)-10(-4) mole/liter, while at concentrations of 10(-3)-10(-2) mole/liter they decreased.

[The effect of taurine on the electrically controlled ion channels of the somatic membrane of pond snail neurons].

Isolated and internally dialysed neurons from the molluscs Lymnaea stagnalis were investigated under voltage-clamp conditions. The increasing of taurin concentration (from 1.10(-8) to 1.

[Comparative characteristics of the membrane mechanisms of the action of fenamine and its derivatives on the ion channels of isolated mollusk neurons].

Phenamine (10(-12)-10(-5) M/l) increased by 20-60 per cent the input (sodium and calcium) currents (Iin), the output slow potassium (Ikm) and fast potassium (Ikb) ones, and decreased the currents in higher concentrations. The volt-ampere characteristics of the membrane (VAC) and the curves of stationary inactivation (CSI) shifted along the potentials axis. The phenamine analogue IEM 1365 only decreased the currents leaving the VAC and CSI unaltered.