Abstract:

Embryos were exposed to high-energy water accommodated fractions (HEWAFs). The ammonia and urea transporters gene expression changes and ammonia and urea excretion rates were measured.

Suggested Citation:

Wang, Y.. 2019. The effect of oil-exposure on urea and ammonia transporters in mahi-mahi (Coryphaena hippurus). Distributed by: GRIIDC, Harte Research Institute, Texas A&M University–Corpus Christi. doi:10.7266/n7-q77z-bm73

Publications:

Wang, Y., Pasparakis, C., Stieglitz, J. D., Benetti, D. D., & Grosell, M. (2019). The effects of Deepwater Horizon crude oil on ammonia and urea handling in mahi-mahi (Coryphaena hippurus) early life stages. Aquatic Toxicology, 216, 105294. doi:10.1016/j.aquatox.2019.105294

Purpose:

Testing the effects of oil exposure on tissue ammonia and urea concentrations, ammonia and urea excretion rates, and mRNA changes of relevant transporters during the development.

Data Parameters and Units:

The dataset contains 4 excel files - “Raw and Corrected Nitrogenous Waste Excretion.xlsx”, “ALS analysis.xlsx”, “qPCR data.xlsx”, and “Raw and Corrected tissue concentration.xlsx” organized under separate folders. Dataset contains the following: Tissue ammonia and urea concentrations (pmol N indiv-1) at different time points (30, 42, 48, 102 hpf); Ammonia and urea excretion rates (pmol N indiv-1 min -1) at different time points (30, 36,42, 48, 54, 72, 78, 96, 102 hpf); mRNA expression of different transporters (Rhag, Rhbg, Rhcg1, Rhcg2, Nhe2, Nhe3, UT) quantified in mahi embryos and larvae in different time points (30,36,42,48,54,78,102 hpf); and PAHs measurements of each experiment. The curve data was calculated by the software and included under each gene file. HPF means hours post fertilization. The unit for concentration is µM. The dataset includes: time points, concentration (Conc., µM), standard deviation (StDev), client, project, service request, sample, lab code, sample type, date collected, date received, date extracted, date analyzed, extraction method, method, matrix, basis, units, component, dilution factor, reporting limit, detection limit, result, result notes, plate A-L, sampleS, read1, read2, avg, StDev, Conc, dilution factor, *2, volume, finale (umol individual-1), pmol N indiv-1, average, stdev, sample, ammonia concentration, urea concentration, total nitrogenous, waste concentration, total nitrogenous average, total nitrogenous stdev, total volume (ml), final umol indv-1, pmol N indiv-1, average, and stdev. The file “qPCR data.xlsx” includes a readme worksheet with headers and descriptions. Note: Blank cells indicate that there is no data for those cells.

Methods:

The oil from the surface (referred to as OFS) used to prepare all HEWAFs (high-energy water accommodated fraction) described herein was collected via skimming operations from surface waters by British Petroleum for testing purposes, and subsequently transferred under a chain of custody to the University of Miami (sample ID: OFS-20100719-Juniper-001 A0087M). Each HEWAF was prepared on the day of use by mixing 1g of oil per liter of filtered, UV-sterilized seawater and mixed in a Waring CB15 blender (Torrington, CT) at low speed for 30s. The mixture was immediately transferred to a glass separatory funnel and settled down for 1h. The lower 90% of the mixture was collected and used for the subsequent experiment as 100% WAF (unfiltered) that was then diluted to nominal concentrations of 2, 4 or 6% using filtered UV-sterilized seawater. Dilution solutions were mixed on a stir plate at 180 rpm for 5 mins and then aliquoted for exposures. Approximately 400 embryos were raised in multiple 20L tanks and samples were collected at different time points when needed for all experiments. There are triplicates for each time points. Water quality was taken daily. Gene expression changes, and ammonia and urea excretion rates were examined after the exposure of fertilized cells to HEWAF. Tissue ammonia and urea concentrations were determined by ammonia assay kit (sigma AA0100) and Diacetyl Monoxime method respectively. Ammonia and urea excretion rates were determined with Micromodified Indophenol Blue and Diacetyl Monoxime methods respectively. mRNA expression raw data analysis was performed with the qPCR Miner software (Zhao and Fernald, 2005) and normalized to EF1a mRNA expression.

Instruments:

qPCR - Stratagene Mx3005P

Provenance and Historical References:

Zhao, S., & Fernald, R. D. (2005). Comprehensive Algorithm for Quantitative Real-Time Polymerase Chain Reaction. Journal of Computational Biology, 12(8), 1047–1064. doi:10.1089/cmb.2005.12.1047

Individual Files: