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Influence Of 2,5-Hexanedione, Acrylamide, Tri-O-Tolyl Phosphate, Leptophos And Methylmercury On Endogenous Levels Of Tryptophan, Serotonin And 5-Hydroxyindoleacetic Acid And Serotonin Turnover Rates In Rat Brain, Craig H. Farr

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Several industrial and environmental chemicals cause distal and/or central neuropathy among other diverse toxic effects. Spague-Dawley derived rats were fed doses of 2,5-hexanedione, acrylamide, tri-o-tolyl phosphate, Leptophos and methylmercury via gavage. The dose levels and administration periods were established in previous experiments designed to assess clinical neuropathy using rats trained to walk on a rotorod apparatus fitted with an electrode floor. After intravenous injections of ³H-Tryptophan, whole rat brain homogenates were analyzed using liquid scintillation and spectrofluorometric techniques for levels of tryptophan, serotonin and 5-hydroxyindoleacetic acid. Serotonin turnover rates were calculated using the specific activities of tryptophan and serotonin …

Alterations In Rat Brain Norepinephrine And Dopamine Levels And Synthesis Rates In Response To Five Neurotoxic Chemicals: Acrylamide, 2,5-Hexanedione, Tri-O-Tolyl Phosphate, Leptophos, And Methyl Mercuric Chloride, Charles N. Aldous

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Acrylamide, 2,5-hexanedione, Tri-o-tolyl phosphate and leptophos belong to three fundamentally different chemical classes but all four chemicals cause central-peripheral distal axonopathy. Some of these compounds have been shown to alter brain steady state levels of neurotransmitters or to inhibit the activities of adenosine triphosphatases which are involved in the uptake and storage of biogenic amines. Tests were performed to determine alterations in steady state levels of rat brain norepinephrine and dopamine in response to doses of the above chemicals and of the central nervous system toxin, methyl mercuric chloride sufficient to cause ataxia. Catecholamine synthesis rate constant estimations were performed. …

Pesticide Exposure Studies: Direct And Indirect Detection Of Absorption Of 2,4-D And Pronamide Herbicides In The Guinea Pig And Occupationally Exposed Workers, Ibrahim A.R. Al-Jabery

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A simple high pressure liquid chromatography procedure was used to determine 2,4-D and pronamide exposure in spraymen and their dermal absorption and excretion in guinea pigs.

Results of dermal application of these herbicides to guinea pigs demonstrated a strong correlation between the applied dermal dose and the urinary residue excretion over the dosage range tested. As the dosage was increased, the urinary excretion of residues was also increased. However, the excretion of 2,4-D amine mixture following dermal treatment of guinea pigs was prolonged as compared to that of pronamide.

Residue levels of these compounds were also determined to estimate skin …