Section on PET Neuroimaging Sciences
Robert B. Innis, MD, PhD, Branch and Section Chief
My laboratory develops and uses positron emission tomographic (PET) radioligands to study pathophysiology in several neuropsychiatric disorders. Working in close collaboration with the radiochemistry laboratory of Dr. Victor Pike, we use in vivo imaging to evaluate novel PET radioligands, first in animals, then in healthy human subjects, and finally in patients. My laboratory has multidisciplinary expertise in pharmacology, animal experimentation, clinical neuroscience, digital image analysis, and human evaluation of investigational radiopharmaceuticals. In addition to traditional receptor targets, we use radiolabeled probes for in vivo imaging of intracellular signal transduction (e.g., cAMP phosphodiesterase), gene expression (e.g., dopamine transporters expressed on transplanted embryonic stem cells), and a mitochondrial protein that is a marker for inflammatory cells (activated microglia and macrophages).
I strongly emphasize training and career development for everyone in my laboratory, whether the person is here for a time-limited period (e.g., graduate student or postdoctoral fellow) or a permanent staff position (e.g., Staff Scientist). I frequently give lectures to the group on ad hoc topics and also teach two courses: writing a scientific paper and pharmacokinetic modeling. In addition, the laboratory has a journal club, project meetings, and thumbnail presentations. Trainees improve their skills at verbal presentation at these laboratory meetings as well as at formal NIH-wide venues and international meetings.
I am fortunate to have outstanding people in my laboratory at different levels of career development, from graduate students to senior investigators (see People, below). For example, as of July 2012, my laboratory has a graduate student in the joint PhD program in neuroscience between NIH and the Karolinska Institutet (Stockholm, Sweden). This jointly mentored PhD program offers outstanding opportunities for training and research for a select group of accomplished and goal-directed students who are expected to emerge as future leaders. In addition, my laboratory has attracted several MD/PhD investigators because of its translational work and has physicians from three medical specialties: psychiatry, neurology, and nuclear medicine.
Imaging is performed in primates and rodents to assess the utility of new probes and to explore models of human pathophysiology. For example, we imaged the serotonin transporter in adult monkeys with a history of maternal deprivation to explore the role of serotonin in the abnormal behaviors of these animals as adults (Ichise et al., 2006). We have also imaged transgenic mice to demonstrate, for example, the role of arrestin3 in the internalization of D2 dopamine receptors (Skinbjerg et al. 2009).
About one-third of our PET scans are performed in animals, and two-thirds in humans. Our research includes "first-in-human" use of novel PET radioligands - e.g., a new probe for the metabotropic glutamate subtype 5 (mGluR5) receptor, the cannabinoid CB1 receptor, a probe for cellular inflammation, and a substrate for P-glycoprotein transporter at the blood-brain barrier. We are now using these radioligands to study the pathophysiology of several neuropsychiatric disorders, including major depressive disorder, autism, HIV infection of the brain, schizophrenia, Alzheimer's disease, drug and alcohol abuse, and epilepsy.
Robert B. Innis, MD, PhD
Chief, Molecular Imaging Branch, NIMH
Bldg. 10, Rm. B1D43
10 Center Drive MSC 1026
Bethesda, MD 20892-1026
Office Tel: 301-594-1368
E-mail Dr. Innis
Branch Administrative Manager:
E-mail Ms. Alzona