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Research Poster PresentationsP O S T E R 5 9Efficacy of Taurine in AlteringSomatostatin and Gad Levels in aPancreatic ß Cell LineChristina CuttittaFaculty Mentor: Dr. William L'AmoreauxDepartment of BiologyRelease of insulin and glucagon from the endocrinepancreas is regulated by a number ofneurotransmitters, including glutamate, GABA, andsomatostatin. In the GABAergic system, GABAbinding to GABAA receptors opens chloridechannels on α cells, hyperpolarizing these cellsthereby regulating glucagon release. We havepreviously shown that taurine treatment altersglucose homeostasis and alters insulin and GABAlevels in a pancreatic β cell line (Hit-T15). Here, wetest the efficacy of taurine in altering somatostatinand GAD expression in Hit cells. In pancreaticislets, glucose uptake serves as an electrogenicswitch to regulate insulin and GABA release. Withconcentrations > 2.8 mM, glucose uptake andglycolytic processing increases cytoplasmic ATPconcentrations, shutting off ATP-sensitive K+channels. Inhibition of the KATP channels increaseCa2+ currents required for exocytosis. We testedwhether taurine treatment can affect somatostatinrelease and whether taurine directly affects GADexpression in β cells. The β cell line were grown inculture, and treated with either 1 mM glucose, 3mM glucose, and 1 mM taurine. Cells were treatedfor 24hr, fixed and prepared forimmunohistochemical analyses. Our data show thatwhile 3 mM glucose significantly decreasessomatostatin and increases GAD levels compared tocontrols, 1 mM taurine is insufficient to elicit thisresponse. Since taurine has been reported to affectrelease of insulin and GABA from large dense corevesicles, we demonstrate here that the mechanismby which taurine promotes exocytosis of thesevesicles is different from the mechanism by whichsomatostatin is released. Further, we provideevidence that the taurine-dependent upregulationof GAD expression requires a feedback mechanismfrom α cells.P O S T E R 6 0Laser Control BoardValerie DeAngeloFaculty Mentor: Dr. Jessica JiangDepartment of Engineering Science and PhysicsA tunable laser is a laser whose wavelength can beadjusted and controlled over a certain range. Thetunable laser used in this project is an EmcoreTTX1994 tunable laser that “consists of a cooledexternal-cavity diode laser that uses thermallytuned etalon filters to achieve single-modeoperation at selectable wavelengths.” (EmcoreDatasheet)This project consists of designing and building aninterface board to power the tunable laser assemblyand allow communication to it through the use of a3 wire RS 232 interface. The tunable laser interfaceboard will send commands to the tunable laserassembly as well as monitor it’s health and alarms,and detect any faults in the tunable laser’s system.54