Effect of Talampanel (an AMPA Receptor Blocker) on Brain Activity

Study Summary

This study will use transcranial magnetic stimulation (TMS) and electroencephalography (EEG) to test the safety of an experimental anti-epileptic drug called Talampanel and learn how it affects brain activity. Talampanel blocks a type of brain receptor called AMPA; inhibiting this receptor may result in anti-seizure activity. TMS stimulates the outer part of the brain, called the cortex. For this procedure, an insulated wire coil is placed on the subject's scalp. A brief electrical current is passed through the coil, creating a magnetic pulse that stimulates the brain. This may cause a pulling sensation on the skin under the coil and muscle twitching in the face, arm, or leg. EEG records the electrical activity of the brain, in the form of brain waves. For this procedure, electrodes (metal discs with a conductive gel) attached to wires are affixed to the scalp with a paste and the brain activity is recorded. Healthy normal volunteers between 18 and 45 years of age may participate in this study. Candidates will be screened with a physical and neurological examination, electrocardiogram (EKG), blood tests, and blood pressure measurement. Women who are pregnant or nursing are excluded from the study. Participants will come to the NIH Clinical Center for three testing sessions, at least 1 week apart, and a final follow-up visit. The procedure for each test session is as follows: 7 AM - Blood pressure is measured, EKG and EEC leads are placed, a heparin lock is inserted, and a blood sample is drawn. The heparin lock is a thin needle enclosed in a thin plastic tube. The needle guides the tube into a vein and is then removed, leaving the tube in place. The indwelling tube allows multiple blood samples to be drawn without repeated needle sticks. 8 - 9 AM - TMS followed by EEG recording. 9 AM - Administration of Talampanel or placebo (pill with no active ingredient) by mouth. 10 AM - Blood sample #2. 10 AM -11 AM - TMS, followed by EEG recording every 5 minutes. 11

Interventions

• DRUG Talampanel