The specific goal of this project is to understand the mechanisms by which toadfish are able to tolerate extreme concentrations of ammonia. To this end, I will determine the metabolic fate of 15NH4C1 in the gulf toadfish, O. beta. This species of fish is known to withstand millimolar amounts of ammonia, whereas mammals can only withstand micromolar ammonia concentrations. By studying the mechanism of ammonia metabolism in the gulf toadfish, a model can be developed to understand ammonia detoxification and tolerance in general. Using this model, treatments may be developed for hyperammonemia in humans, which may be caused by a number of factors, including exposure to pollutants. In this work, the products generated by ammonia metabolism will be isolated. The levels of 15N in each product will then be determined using isotope ratio mass spectrometry. In addition, to location of these products in various organs will also be determined.
