Optogenetic Stimulation of Nucleus Accumbens Shell Dopamine D2 Receptor-Containing Medium Spiny Neurons Attenuates Cocaine-Prime

Ayanna conducting lab research




Post-Doc, Pierce Labs

Project Summary

In the Pierce Lab, the neural mechanisms underlying cocaine addiction and relapse, an issue that is very prevalent in today’s society, are modeled and studied. The goal of my project was to test optogenetic techniques on neurons that contain either D1 dopamine receptors or D2 dopamine receptors. Optogenetics is the use of light to stimulate specific populations of neurons. We chose to use optogenetic stimulation similar to the frequency of deep brain stimulation (DBS) because DBS is anFDA approved technique used to treat many neurodegenerative disorders and is known to suppress cocaine seeking in models of relapse in rats. The medium-spiny neuron (MSN) population containing D1 dopamine receptors is known as the direct, excitatory pathway in which potentiates addictive behaviors. The neuron population containing D2 dopamine receptors is known as the indirect, inhibitory pathway in which suppresses addictive behaviors. Knowing this, we hypothesized that high frequency stimulation of the D1-MSNs would increase cocaine-primed reinstatement of cocaine seeking while this same stimulation in D2-MSNs would decrease cocaine-primed reinstatement of cocaine seeking.

Through my experience in the Pierce Lab, I learned the importance of careful planning and attention to detail when conducting research. Every action, test, mistake, etc. needs to be accounted for in order to keep the lines of communication open between lab members while also keeping the experiment running smoothly. It is important to do tasks correctly and precisely the first time, especially working with live animals, because small mistakes add up and become costly to the outcome of the experiment. I was also able to learn so many new lab techniques this summer, such as intraperitoneal injections, setting up and using the laser for optogenetics and qPCR.

As a BBB minor, I have learned so much about both the behavioral and biological aspects of neuroscience. In that I can fit so few BBB classes into my schedule, my experience in the Pierce lab has been pivotal in allowing me to explore a topic in more depth than I could have ever imagined. I learned how to think critically about both the research I was doing as well as complex scientific topics. This experience has definitely increased my confidence in my ability to participate in and thoroughly understand higher level research topics and techniques. My experience within the Pierce Lab will ultimately help me to have the proper skills and knowledge to pursue independent research during my Junior year and has helped me to decide that I would like research to be a part of my future career.