Catecholaminergic neurons of the A2 area play a prominent role in brainstem vagal circuits. It is not clear, however, if these neurons are noradrenergic/adrenergic (i.e. display tyrosine hydroxylase (TH) and dopamine--hydroxylase (DH) immunoreactivity (-IR) or dopaminergic (i.e TH- but not DH-IR). Our aims were to investigate whether a subpopulation of neurons in the A2 area was dopaminergic and, if so, to investigate the effects of dopamine (DA) on the membrane of gastric-projecting vagal motoneurons. We observed that while the majority of A2 neurons were both TH- and DH-IR, a small percentage of NTS neurons were TH-IR only, suggesting that DA itself may play role in these circuits. Whole cell recordings from thin brainstem slices, showed that 71% of identified gastric-projecting motoneurons responded to DA (1-300µM) with either an excitation (28%) or an inhibition (43%) of the membrane; the remaining 29% of the neurons were unresponsive. The DA-induced depolarization was mimicked by SK38393 and prevented by pretreatment with SCH23390. Conversely, the DA-induced inhibition was mimicked by bromoergocryptine and prevented by pretreatment with L741626. When tested on the same neuron, the effects of DA and NE were not always similar. In fact, in neurons in which DA induced a membrane depolarization, 77% were inhibited by NE, while 75% of neurons unresponsive to DA were inhibited by NE. Our data suggest that DA modulates the membrane properties of gastric-projecting motoneurons via D1- and D2-like receptors, and DA may play different roles than NE in brainstem vagal circuits.