Chemical profiles and monitoring dynamics at an individual nerve cell in Planorbis corneus with electrochemical detection

The identified dopamine cell of Planorbis corneus is described as a model s ystem to study neurotransmitter storage and dynamics. Techniques developed with this model system include capillary electrophoresis with electrochemic al detection and microelectrochemistry at single cells. These techniques pr ovide a powerful combination to examine single cell neurochemistry. Whole c ell and cytoplasmic dopamine concentrations have been quantified with capil lary electrophoresis. Additionally, this technique has been used to profile amino acids and to quantify two compartments of neurotransmitter in a sing le cell. Individual exocytosis events have been monitored at the cell body of the dopamine cell of P. corneus with microelectrodes. In this case, two different types of vesicles have been identified based on the amount of tra nsmitter released. The psychostimulant, amphetamine, has been shown to sele ctively affect the amount of dopamine in these vesicles with lower to highe r doses affecting the larger to smaller vesicle types, respectively. Microe lectrochemistry at single nerve cells has also been used to demonstrate rev erse transport of dopamine across the cell membrane and to suggest a role o f this process in the molecular mechanism of amphetamine. (C) 1999 Elsevier Science B.V. All rights reserved.