Andrew Lamprecht and Scott Steffensen, Psychology

Introduction

Methamphetamine is an extremely addictive drug that acts on the pleasure center of the brain. It causes an increase in the release of dopamine (DA) into the synaptic cleft. This rapid release of DA causes the “rush” felt by drug users. It also causes severe malfunctions in the brain such as anxiety, mood disorders, increased violence, reduced motor skills, impaired verbal learning, and psychosis. Among other things, the cause for these harmful effects could be related to Reactive Oxygen Species (ROS) and their resulting oxidative damage. Oxidative damage has been suggested to constitute early signaling events in programmed cell death, contributing to the idea that it may be the primary source of damage done to the neural tissue from Meth.

However, the mechanism by which this happens is not completely understood yet. One step to understanding this process and, in turn, being able to determine how to prevent it, is knowing where and when ROS are being produced in the striatum after neural tissue is exposed to methamphetamine. Understanding this enables us to know better what methamphetamine is acting on (mechanistically) and how it is affecting the surrounding systems (chemically).

Methodology

In order to locate where and when this process is happening, we used high speed imaging techniques to pinpoint the regions of ROS production. We superfused a fluorescent probe selective to hydrogen peroxide over brain slices under high magnification. After a brief wash, we superfused methamphetamine across the slice while monitoring the system with an Andor high-speed camera. As the figure contained shows, our preliminary experiments with methamphetamine helped us determine the EC50, which helped us determine the exact concentration of methamphetamine to use for the experiment. If methamphetamine exposure causes production of hydrogen peroxide, the dye will fluoresce where it is produced. We split the frames up into nanosecond exposure times and focused in on different parts of the striatum, pinpointing when and where the ROS were produced.

Results

Multiple trials were realized in order to produce consistent results. However, we were never able to produce a significant amount of fluorescence in order to identify any real trends. We adjusted the frame rate and the exposure of the Andor camera, and we did everything we possibly could to keep any alternate light sources from polluting our sample. Despite all these efforts, no consistent fluorescence was observed.

Discussion

The main reason for the lack of success in the experiment I carried out was the lack of consistent reliability of the results of prior experiments done in our lab, on which my experiment was predicated. Results of experiments done in Scott Steffensen’s lab done previous or concurrent to mine indicated that methamphetamine exposure did produce Reactive Oxygen Species. However, as I began preparing to carry out my project, these results began to be difficult to replicate. We already doubted these prior conclusions heading into the actual execution of my methods. This made it difficult to pursue my project because we needed concrete data to use in order to carry out my project.

Conclusion

My project is still ongoing and will still provide very useful information if we can obtain constant results from the experiments it is predicated on. I continue to work in Dr Steffensen’s lab on other projects, contributing to further understanding of the addiction process. I hope to be able to return to my project in high-speed Andor camera imaging with reliable data to work with soon. I do believe that Meth does create ROS, and that these are integral in the negative impacts of Methamphetamine on the brain.

Although my project was not a traditional success in producing consistent results yet, I have learned a lot from my experience. First, the opportunity to write up an abstract and a project report has increased my technical writing skills. From here on out, if I were asked to write up a formal technological report, I would feel confident in my abilities to do it. Second, I learned how to operate the Andor High-Speed Camera. This is a unique and valuable laboratory skill that will be extremely marketable if I do decide to go into research professionally. Finally, I have learned how to manage the steps of carrying out a project in a research environment. This includes forming the initial idea and hypothesis, preparing the methods and materials, and executing the project with the help of others.

I am extremely grateful for the opportunity I have been given to work on this project, and for the lessons and skills I have learned from this experience. I hope that these will serve me to be able contribute greatly to the furthering of modern science in the near future.