Many drugs that effect human mood and/or thought act by mimicking or inhibiting the actions of neurons in the brain. Nerves function by releasing chemicals (neurotransmitters) that interact with sites (receptors) on other neurons in the brain. An important type of neuron in the brain produces and releases the substance serotonin; serotonin interacts with "serotonin receptors" located on other neurons adjacent to the serotonin-producing neuron. Dr. Teitler has established the role of serotonergic systems in control of mood and cognition as well as the serotonergic mechanisms of anti-migraine, anti-nausea, anti-psychotic, and hallucinogenic drugs. Dr. Teitler is currently pursuing the discovery of novel drugs directed at serotonin receptors and their functions in the brain and periphery. Underlying Dr. Teitler's research program is a belief that the receptor multiplicity for all neuroactive substances will lead to new insights into biological systems and to the development of new and/or improved drug therapies for all diseases. Site-specific mutagenesis to produce mutant forms of serotonin receptors in vitro has revealed novel properties of antipsychotic drugs: this work has potential implications for uncovering the etiology of mental diseases and for the development of novel antipsychotic medications. Recently important anti-psychotic drugs, such as risperidone (Risperdal), have been found to produce unique effects on cells expressing serotonin receptors. The exploration of these unique effects are revealing a new class of drugs, novel molecular mechanisms for receptor regulation, and the possibility of a new class of therapeutics for many diseases. In addition, the understudied properties of the "5-HT1E" receptor, discovered in Dr. Teitler's laboratory, are being explored with an emphasis on the development of the first drugs designed to selectively stimulate or block this receptor. These drugs should aid in understanding the function of the 5-HT1E receptor and may have novel therapeutic properties.