In vivo voltammetric measurement of evoked extracellular dopamine in the rat basolateral amygdaloid nucleus.

1. The in vivo measurement of evoked extracellular dopamine was established in the basolateral amygdaloid nucleus (BAN) using fast-scan cyclic voltammetry at carbon-fibre microelectrodes. 2. The identification of evoked extracellular dopamine in the BAN was based on anatomical, electrochemical and pharmacological criteria. Electrochemical and pharmacological evidence indicated that the species was a catecholamine. Mesencephalic sites eliciting overflow and amygdaloid sites supporting overflow correlated well with the mesoamygdaloid dopamine innervation. 3. Marked differences in the dynamics and magnitude of evoked dopamine overflow were observed in the BAN, caudate-putamen and amygdalo-striatal transition area. The results underscore the importance of making spatially resolved measurements of extracellular dopamine in the amygdala. 4. Mesoamygdaloid dopamine neurons have similar release characteristics as mesostriatal dopamine neurons but share with mesoprefrontal cortical dopamine neurons the ability to use a greater percentage of intraneuronal dopamine stores for release.