Discipline: Biological Sciences
Subcategory: Physiology and Health
Alexis Richardson - Southern University at New Orleans
Co-Author(s): Dominique Catalano, Westchester University, Westchester, PA; Jessica Marinari, Westchester University, Westchester, PA; Shabee Bukhari, Westchester University, Westchester, PA; Maurice Hunt, Westchester University, Westchester, PA; On? R. Pag?n, Westchester University, Westchester, PA.
Planarians are invertebrate organisms that have what has been described as a ‘primitive’ brain that possess some features common of a vertebrate central nervous system (i.e., multipolar neurons and dendritic spines). Planaria also have environmental preferences that are crucial to their survival. One of those is the preference for dark environments that allow them to remain safe from predators. In previous studies planaria have displayed addictive behaviors similar to those of humans when exposed to nicotine over a period of time. Our hypothesis was that if introduced to nicotine under nontraditional environmental preferences (i.e. light versus dark) that the test subjects environmental preferences would change without any significant change in motility. To determine if the environmental preferences could be influenced fifteen planaria were exposed to light over an 18-hour period. Six of them were in a solution of 20uM nicotine and 5 mL of APW (artificial pond water) the remaining nine were in a solution of 0.5% dimethylsulfoxide (DMSO) and 5mL APW. Each specimen was placed into a petri dish that was covered hallway with black tape. The specimens were then observed under both light and dark conditions for ten minutes each. What we observed was that six specimens who were exposed to the 20uM of nicotine spent 40% more time in the light while the nine specimens that were not exposed to nicotine showed no changes in environmental preference. When the worms are exposed to low concentrations of nicotine (20 uM) over a period of 18 hours, their environmental preference (dark) is significantly diminished without any apparent effect on motility. From our data we can conclude that when exposed to nicotine, planarians natural environmental preferences are changed, presumably in a way reminiscent to addictive behaviors. In our future research this data will be used as a tool to determine if Cembranoid (4R), a nicotine antagonist, can be used to reverse the changes induced by the nicotine therefore effectively reversing addictive-like behavior.
Funder Acknowledgement(s): This research project was funded by National Institutes of Health NIDA grant R03DA026518. Summer internship for Ms. Alexis Richardson was sponsored by Southern University at New Orleans (SUNO) US Department of Education Minority Science and Engineering Improvement Program (MSEIP) - Capacity Competitiveness Enhancement Model (CCEM) grant P120A160047.
Faculty Advisor: Dr. Murty Kambhampati, mKambham@suno.edu
Role: I ran all of the experiments over the span of two weeks. Including care of all test specimens, set up of all lighting and testing areas as well as making all nicotine stocks.