Gerhardt Laboratory

Overarching Mission of the Gerhardt Laboratory:

The Major mission of the Gerhardt Lab is to develop Brain Machine Interface (BMI) medical technologies involving implantations of catheters (Parkinson’s studies), microelectrodes (MEA’s for chemical and electrophysiological recordings) and combined closed-loop technologies for the understanding and treatment of brain disorders.

Parkinson’s Disease:

Dr. Gerhardt’s laboratory focuses on studies of movement abnormalities in aging, specifically Parkinson’s disease and parkinsonism.  Such studies are performed in the striatum of young and aged Fischer 344 rats, and in young and aged nonhuman primates. For these studies, his lab uses both the 6-hydroxydopamine-lesioned rat model and the MPTP-lesioned primate model of Parkinson’s disease.  Using his microelectrode techniques, Dr. Gerhardt’s lab has investigated the release and uptake of dopamine in the striatum of the normal and parkinsonian brain.  A major finding for these studies is that there is a severe disruption of dopamine regulation in the parkinsonian brain.  This disruption of the control of dopamine may relate to some of the movement problems seen in this CNS disease.  His laboratory has been investigating the use of growth factors, such as GDNF, to restore function to damaged dopamine neurons in Parkinson’s disease. His group was instrumental in the Phase I/II clinical studies of patients with Parkinson’s disease that was carried out at his Udall Center and was sponsored by Amgen. Additional pre-clinical studies are now underway with a new venture with Medtronic and Eli Lilly to get GDNF back into clinical trials in the next 2 years. Dr. Gerhardt was awarded a Research Career Development Award (RCDA; 1989-1994) from the NIA and he also received a Level II Research Scientist Development award (RSDA; 1995-2000) from the NIA. He has had consistent NIH funding at the RO1 and PO1 or P50 levels throughout his career. In addition, he has directed a T32 Training grant with 4 pre-doctoral and 2 postdoctoral slots from NIA since 2009.

Normal Aging:

His additional studies in normal aging have shown that, dopamine and norepinephrine synapses change in their ability to regulate neurotransmitter release through changes in the monoamine transporters.  In addition, recent work from his group has determined dynamic age-related changes in glutamate regulation in the rat striatum, frontal cortex  and hippocampus. These studies are the first to look at second-by-second regulation of glutamate in sub-regions of the rat frontal cortex, striatum and hippocampus that are involved with Parkinson’s disease and Alzheimer’s disease and other age-related disorders of the CNS.

Neuropharmacology:

Historically, Dr. Gerhardt’s research group has also been extensively involved in neuropsychopharmacology and the development of new drugs to treat depression, mania, schizophrenia and attention deficit hyperactivity disorder (ADHD). Dr. Gerhardt was awarded a 5-year KO2 (RSDA) from NIMH from 2000-2005.

MEA Sensor Technology:

A major technology development focus of Dr. Gerhardt’s laboratory is the dynamics of neurotransmitter function in the central nervous system.  In order to perform such studies, his lab develops microelectrode arrays (MEAs)and instrumentation for the rapid, sensitive, and spatially resolved measurement of neurotransmitters and neuromodulators, such as dopamine, norepinephrine, serotonin, nitric oxide, glutamate, GABA, acetylcholine, ATP and adenosine.  His lab developed the ceramic-based microelectrode array technology that is currently being used in his laboratory and others to better understand rapid neurotransmitter signaling in the normal, aged and diseased brain. A major goal of these studies is to understand neurotransmitter signaling in biological systems on a second-by-second time scale.  This forms the basis for the Center for Microelectrode Technology, which was started with a mandate from NSF in 1991. In addition, his laboratory designs the MEAs that are being used to develop the BMI device with Dr. Ted Berger (USC) and Dr. Sam Deadwyler (Wake Forest) to repair the hippocampus in memory impaired animals and may lead to a cortical prosthetic device for use in humans. This is currently funding by the DARPA in the form of a multi-university grant.

Research Interests:

• Brain grafting and tissue regeneration
• Trophic Factors
• Aging of the CNS
• Parkinson’s disease
• Neuropharmacology
• Depression, Anxiety
• Schizophrenia
• Alzheimer’s disease
• High performance liquid chromatography(HPLC) applications
• Drug pharmacology
• Attention Deficit Hyperactivity Disorder
• High-speed in vivo electrochemistry
• Electroanalytical instrumentation
• Brain Machine Interfaces
• Microelectrode technologies