My research is focused on understanding neuronal mechanisms of synaptic plasticity involved in pain and drug addiction circuits. One area of current research is focused on identifying intracellular signaling pathways involved in morphine tolerance and dependence using in vitro brain-slice recordings and in vivo behavioral assays. Our experiments focus on how mu opioid receptors (MOPrs) in the periaqueductal gray area (PAG) modulate neuronal excitability and synaptic transmission of PAG neurons. MOPrs are an integral part of the endogenous descending antinociceptive pathway that decreases pain impulses in the spinal cord. Repeated and continuous opioid administration induces neural changes in this system. A second area of research in my laboratory is the dopamine transporter (DAT) and an associated chloride current that I identified in midbrain dopamine neurons. The DAT is one of a family of transporters that are the main targets for psychostimulants, such as amphetamine and cocaine. These transporters are also targets for therapeutic drugs for disorders including depression and attention deficit disorder. Although the transporters are primarily known for regulating extracellular concentrations of neurotransmitters through reuptake of released neurotransmitters, they have significant electrical activities as well. My recent studies determined that these transporters have a role in modulating excitability of midbrain neurons.
- B.A., Bowdoin College, Brunswick Maine 1990
- Ph.D., Oregon Health & Science University, Portland Oregon 1996