Professor EmeritusResearch Interests: Neurochemistry; Neuropharmacology; Hypothalamic-Pituitary-Adrenal AxisDetailsBiography We are interested in the development of the monoaminergic neurotransmitter systems (i.e., dopamine, DA; serotonin, 5-HT; and norepinephrine, NE) and how these systems are influenced by early exposure to drugs of abuse or compounds used in the treatment of psychopathological disorders. Much of our recent work has involved the use of a rat model to determine the mechanisms of cocaine action on the developing brain and the neurochemical and behavioral consequences of chronic prenatal cocaine exposure. Previous studies had shown that cocaine binds to the plasma membrane transporters for DA, NE, and 5-HT, thereby blocking the synaptic reuptake of these transmitters and potentiating their activity. We have determined the pharmacological characteristics and distribution of these transporters in fetal and adult brain using several radioligands, including the cocaine analog [125I]RTI-55 (which binds to both DA and 5-HT transporters) as well as other drugs that more selectively label individual transporter subtypes. Another possible target of developmental cocaine action is the placenta, which expresses both transporters and receptors for NE and 5-HT. We have investigated the normal distribution of placental transporters using in vitro autoradiography, and we have also shown that maternal cocaine treatment up-regulates the placental NE transporter and may down-regulate the ß-adrenergic receptor system. Current lab projects include the effects of prenatal cocaine treatment on signal transduction mechanisms and modulation of DA-regulated neuropeptide gene expression in the brain.