BURSTING FIRING OF ACTION-POTENTIALS IN CENTRAL SNAIL NEURONS ELICITED BY D-AMPHETAMINE - ROLE OF THE INTRACELLULAR CALCIUM-IONS

The role of the intracellular calcium ions on the bursting firing of a ction potentials in central snail neutrons elicited by d-amphetamine w as studied in the identified RP4 neuron of the African snail, Achatina fulica Ferussac. Bursting activity of the potentials was elicited by d-amphetamine in central RP4 neuron of snail ii amphetamine was applie d either extracellularly or intracellularly. The bursting firing of ac tion potentials elicited by amphetamine was decreased following intrac ellular injection with either EGTA or magnesium ions or extracellular application of lanthanum ion. Intracellular injection of calcium ions elicited bursting activity of potentials in the RP4 neuron, however, i ntracellular injection of calcium ions did not prolong the duration of the bursting firing of action potentials elicited by amphetamine. W7 (N-(6-aminohexyl)-5-chloronayhtha lenesulfonamide hydrochloride), a ca lmodulin antagonist, dill not decrease the bursting firing of action p otentials elicited by amphetamine, although W7 did decrease the bursti ng firing of action potentials elicited by pentylenetetrazol. It is co ncluded that the bursting activity oi potentials elicited by amphetami ne is associated with intracellular calcium ions.