Presentation Type

Oral Presentation

Department

Biology

Major

Biology

Abstract

Pollutants can change the behaviors of invertebrate stream animals. The level of one common pollutant, nitrate (NO3), has been rising in many local rivers and streams throughout the United States due to increases in anthropogenic sources. Nitrate, heavily regulated for its toxic effects to human health, namely the aiding in the development of cancer, also dangerously affects aquatic species by converting oxygen-carrying pigments to forms that are incapable of carrying oxygen. To understand the stress effects of ambient nitrate exposure on P. clarkii, we collected hemolymph samples from red swamp crayfish (Procambarus clarkii) over a 48-hour period after exposure to varying concentrations of nitrate. We measured P. clarkii hemolymph glucose as a proxy for a secondary stress response neuropeptide, crustacean hyperglycemic hormone (cHH), using a custom fabricated high performance liquid chromatography (HPLC) system. The results of our statistical models indicate a significant interaction at 48 hours and 10 ppm, 30 ppm, and 50 ppm relative to 12 hours and 0 ppm (p<0.05). The effect of sex and length also showed a significant effect with exposure to nitrate (p<0.05). While over the 48-hour period the control treatment at 0 ppm decreases in stress response, at 10 ppm, 30 ppm, and 50 ppm the groups continuously maintain elevated glucose concentrations. Hemolymph nitrate levels were directly related to the external concentrations of nitrate in the surrounding water, indicating that crayfish increasingly sequestered nitrates with greater nitrate exposure. Therefore, the accumulation of non-essential ions, specifically nitrate in crayfish hemolymph and tissue, could reflect the concentrations of nitrate pollutants in an aquatic environment contaminated by mixed pollution.

Faculty Mentor

Lee B. Kats

Funding Source or Research Program

Summer Undergraduate Research Program

Presentation Session

Session C

Location

Plaza Classroom 190

Start Date

1-4-2016 5:15 PM

End Date

1-4-2016 5:30 PM

 
Apr 1st, 5:15 PM Apr 1st, 5:30 PM

The effect of nitrate on the release of glucose into the hemolymph of crayfish, Procambarus clarkii

Plaza Classroom 190

Pollutants can change the behaviors of invertebrate stream animals. The level of one common pollutant, nitrate (NO3), has been rising in many local rivers and streams throughout the United States due to increases in anthropogenic sources. Nitrate, heavily regulated for its toxic effects to human health, namely the aiding in the development of cancer, also dangerously affects aquatic species by converting oxygen-carrying pigments to forms that are incapable of carrying oxygen. To understand the stress effects of ambient nitrate exposure on P. clarkii, we collected hemolymph samples from red swamp crayfish (Procambarus clarkii) over a 48-hour period after exposure to varying concentrations of nitrate. We measured P. clarkii hemolymph glucose as a proxy for a secondary stress response neuropeptide, crustacean hyperglycemic hormone (cHH), using a custom fabricated high performance liquid chromatography (HPLC) system. The results of our statistical models indicate a significant interaction at 48 hours and 10 ppm, 30 ppm, and 50 ppm relative to 12 hours and 0 ppm (p<0.05). The effect of sex and length also showed a significant effect with exposure to nitrate (p<0.05). While over the 48-hour period the control treatment at 0 ppm decreases in stress response, at 10 ppm, 30 ppm, and 50 ppm the groups continuously maintain elevated glucose concentrations. Hemolymph nitrate levels were directly related to the external concentrations of nitrate in the surrounding water, indicating that crayfish increasingly sequestered nitrates with greater nitrate exposure. Therefore, the accumulation of non-essential ions, specifically nitrate in crayfish hemolymph and tissue, could reflect the concentrations of nitrate pollutants in an aquatic environment contaminated by mixed pollution.