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Item Investigation of octopamine-glutamate dual transmission neurons(Montana State University - Bozeman, College of Letters & Science, 2020) McKinney, Hannah Margaret; Chairperson, Graduate Committee: Steven R. Stowers; Lewis Sherer, Jessica L. Williams, Sarah Certel and Steven R. Stowers were co-authors of the article, 'Characterization of drosophila mimic-converted octopamine receptor GAL4 lines' in the journal 'Journal of Comparative Neurology' which is contained within this dissertation.; Dissertation contains a paper of which Hannah Margaret McKinney is not the main author.Dual transmission, or the ability of a neuron to signal with more than one neurotransmitter, is now a well-established phenomenon in the field of neuroscience. However, many questions about this type of signaling process still remain with regards to its mechanisms and its impacts on neural circuitry and organism behavior. In particular, the mode of neurotransmitter release from synaptic vesicles can have significant profoundly affects elements on neural circuitry and, subsequently, on behaviors of an organism. In Drosophila melanogaster, a particular subset of neurons important for the behaviors of courtship and aggression signal with the neuromodulator octopamine and the excitatory neurotransmitter glutamate. Whether these two neurotransmitters are released simultaneously (co-release) or are housed for separate synaptic release (cotransmission) is unknown. The mechanism of release for these neurotransmitters in this population of neurons is investigated here through the development of synaptic vesicle visualization tools, synaptic vesicle isolation, and an examination of the expression of octopamine and glutamate receptors; I explored the hypothesis that receptor expression downstream of dual transmitting neurons will provide information about the co-release or co-transmission of octopamine and glutamate. Results from these experiments demonstrated release of octopamine and glutamate from the same synaptic site, with some variation, and a significant amount of presynaptic receptor expression. The results indicate these dual transmission neurons may release octopamine and glutamate at the same synapse for both post-synaptic signaling as well as pre-synaptic signal modulation.Item The effects of L-citrulline supplementation on physical performance(Montana State University - Bozeman, College of Education, Health & Human Development, 2019) Stordahl, Peter Lawrence; Chairperson, Graduate Committee: John G. Seifert; John G. Seifert, Mary Miles and Dawn Tarabochia were co-authors of the article, 'The effects of l-citrulline supplementation on physical performance' submitted to the journal 'Journal of strength and conditioning research' which is contained within this thesis.INTRODUCTION. Recent studies have investigated l-citrulline (CIT) as a possible ergogenic aid. A small number of studies have explored the performance question, with varying methodologies and results. The purpose of this study was to examine CIT influence on cycling time to exhaustion, cardiovascular function, and muscle activity. METHODS. Thirteen healthy subjects volunteered for this study. The first visit was to obtain a maximal power output, where 80% and 50% of maximal power were calculated for the following two visits. Subjects were then randomly assigned into either treatment or placebo groups for the second visit and the opposite treatment for the third visit. Subjects were instructed to drink their treatment 1 hour prior to coming into the laboratory. The treatment drink contained 10g of CIT while the placebo (PBO) was formulated to look and taste like the CIT drink. The second and third visits to the laboratory consisted of EMG from the rectus femoris, vastus medialis, and medial gastrocnemius of the right leg, along with HR monitor and BP. Subjects completed a 40-minute interval ride, consisting of 8 5-minute intervals of 3 minutes at 50% maximal power and 2-minutes at 80% maximal power. After the interval ride, subjects received a second dose of either treatment, 5g of CIT or PBO and were allowed 1-hour rest before the ramped time to exhaustion (TTE) test. RESULTS. There was no significant difference in TTE by treatment (CIT, 20.79 + or - 4.48 and PBO, 20.86 + or - 3.99). There was no significant main effect of treatment on percent of maximum heart rate (p = 0.084), mean arterial pressure (p = 0.714), or muscle activity of the rectus femoris (p =0.300), vastus medialis (p = 0.641), or medial gastrocnemius (p = 0.133) during the TTE test. CONCLUSIONS. There were no differences in cycling TTE between treatments. Further research should investigate the metabolism of CIT under different physiological conditions.Item Application of the thiosulfonate switch technique and a modified biotin switch technique protocols to detect protein S-nitrosothiols in mouse liver lysates in 1D and 2D gel studies(Montana State University - Bozeman, College of Letters & Science, 2015) Miller, Colin Gregory; Chairperson, Graduate Committee: Paul Grieco; Brian Bothner (co-chair)While the role of nitric oxide (NO) in cell signaling and liver growth has been well documented, the identification of S-nitrosylated proteins, one of the major NO transport mechanisms within the cell, remains a challenge. Classically, the implementation of biotin labeling, known as the biotin switch technique (BST), with streptavidin-agarose bead pulldown and subsequent immunoblotting, has offered the best results for identifying S-nitrosocysteine residues within proteins. However, this technique has come under scrutiny for its use of ascorbate as a reducing agent. Numerous published accounts have shown ascorbate's poor reducing potential especially for S-nitrosoproteins. To this end, the Grieco lab has shown that pure S-nitrosylated proteins can be transformed into S-phenylsulfonylcysteine residues, which can be readily converted into mixed disulfides thus allowing for labeling of pure nitrosylated proteins at pH's as low as pH 4. This protocol is referred to as the thiosulfonate switch technique (TST). The Grieco lab has also modified the biotin switch technique to incorporate electrophilic maleimide and orthopyridyl disulfide (OPSS) dyes for fluorescence labeling of the S-nitroso proteome. To examine the scope and limitations of the TST vis-a-vis cell lysates, the TST protocol and the modified BST protocol, both employing novel Z-CyDyes developed in the Grieco Laboratory, have been used to specifically label S-nitrosylated proteins in complex liver lysates. The successful labeling of mouse liver lysates, employing UV and ascorbate SNO knockout negative controls, is demonstrated in both 1D and 2D gel studies. Also reported herein is the creation of novel second generation maleimide dyes (SO3-Cy-Mal) based on Z-CyDyes.Item Fermentation of faba beans (Vicia faba) with Rhizopus oligosporus and Lactobacillus sanfrancisco(Montana State University - Bozeman, College of Education, Health & Human Development, 1982) Centers, Kay NashItem Factors affecting utilization of aspartic acid by Leuconostoc Mesenteroides P-60(Montana State University - Bozeman, College of Letters & Science, 1950) Clark, Richard S.Item Effect of addition of amino acids to barley rations for rats and swine(Montana State University - Bozeman, College of Agriculture, 1962) Davidson, Richard M.Item Protein decomposition products in the soil(Montana State University - Bozeman, College of Letters & Science, 1952) Shafer, CarolItem Bioavailability of three homopoly amino acids in growing rats and chicks(Montana State University - Bozeman, College of Education, Health & Human Development, 1982) Dew, Nancy CrevistonItem Free amino acid content and biosynthesis in eggs of the grasshopper Aulocara Elliotti Thomas during development(Montana State University - Bozeman, College of Agriculture, 1965) Bunde, Daryl Eugene