Nicotine Addiction

Nicotine is the major addictive substance in tobacco. Its action on the nicotinic receptors in the brain is the initial step that sets off a series of transient and persistent adaptive changes eventually leading to addiction.  Similar to many other drugs of abuse, nicotine exploits the so-called “brain reward pathway” that originates in the ventral tegmental area (VTA) and projects to the limbic and cortical structures in the brain.  By modulating both excitatory and inhibitory inputs, acute nicotine increases excitability and plasticity of the dopaminergic (DA) neurons in the reward circuit crucial to the reinforcing effect of nicotine and a number of other psychostimulants.  Recent findings in our lab have revealed a previously unknown phenomenon in the modulation of the inhibitory input to the DA neurons in the VTA.  D1 dopamine receptor, a subtype of dopamine receptors involved in behavioral sensitization and drug self-administration, tonically modulates the inhibitory input to the DA neuron and, moreover, it is required for the acute nicotinic effect on synaptic transmission to the DA neurons.  We propose to further investigate the interaction between nicotinic receptors and D1 receptor sin the inhibitory synaptic input in the VTA under acute, as well as chronic in vivo exposure of nicotine in adult rats.

Other Grants

Lindsay M. De Biase, Ph.D., University of California Los Angeles
The role of microglial lysosomes in selective neuronal vulnerability
Synapses, the sites of signaling between neurons in the brain, play essential roles in learning, memory, and the health of neurons themselves. An enduring mystery is why some neurons are…
How the nervous system constructs internal models of the external world
As animals navigate their environments, they construct internal models of the external sensory world and use these models to guide their behavior. This ability to incorporate ongoing sensory stimuli into…
Xiaojing Gao, Ph.D., Stanford University
When Neural Circuits Meet Molecular Circuits: Quantitative Genetic Manipulation with Single-cell Consistency
Cells are the building blocks of our bodies. We get sick when the cells “misbehave”. The way modern gene therapies work is to introduce genes, fragments of DNA molecules that…
Rafiq Huda, Ph.D., Rutgers University
Conducting the orchestra of movement—functional role of striatal astrocytes in health and disease
Movement requires coordinated activity across a large brain-wide network. The striatum is a particularly important part of this circuit; it integrates motor-related information from many distinct brain regions to regulate…