Contribution of the amygdala and nucleus accumbens to ventral pallidal responses to dopamine agonists

摘要: Neurons recorded from ventral pallidum/substantia innominata (VP) of the basal forebrain respond to dopaminergic agonists that activate either D1 or D2 receptor subtype. Major afferent systems VP originate within amygdaloid nuclei (AMN) and nucleus accumbens (NA). Since both AMN NA are dopaminoceptive, present study sought analyze contribution these responses agonists. Single neurons were electrophysiologically in vivo chloral hydrate-anesthetized rats, following determinations made. (1) Effects pharmacologic inactivation an system assessed by monitoring during intracerebral microinjections local anesthetic procaine, administered directly into NA. (2) With procaine-induced rate changes used indicate influence on neuron, apomorphine (an agonist acts at subtypes), SKF38393 (a agonist), quinpirole agonist) determined compared with rats not receiving procaine pretreatment. Following NA, approximately 80% monitored demonstrated changes, illustrating spontaneous neuronal firing is dependent tonically active input systems. cessation, remained intact, suggesting necessary for responding systemic administration act receptors. In contrast, number responded was diminished follow intra-AMN (but intra-NA) procaine. This suggests D1-induced mediated, least part, via AMN.