Meeting Abstract
The hepatopancreas of crayfish is responsible for filtering and detoxifying the body following xenobiotic exposure. The herbicide atrazine is heavily applied in the Midwestern United States and concentrations in streams and rivers surrounding agricultural areas can reach >300 ppb for upwards of three weeks. We exposed crayfish (Faxonius virlis) to environmentally relevant concentrations of atrazine (0, 10, 40, 80, 100, and 300 ppb) for seven days and examined the effects of atrazine on the cells of the hepatopancreas. We used hematoxylin and eosin staining in addition to TdT mediated dUTP nick-end labelling (TUNEL) to determine if atrazine exposure causes changes in morphology and DNA damage following exposure. We hypothesize that as atrazine exposure concentrations increase; there is an increase in both DNA damage and vacuolization in cells of the hepatopancreas. We expect to see an increase in TUNEL-positive cells as atrazine exposure concentrations increase. Further, we predict that there will be a disintegration of tubular epithelia, dilation of the tubules, and an increase in the number of vacuoles per lobule. Understanding the effects of atrazine and correlating these with accumulation and recovery from exposure to herbicides like atrazine will allow us to assess the long-term effects of atrazine on aquatic organisms. Because detoxification of xenobiotics is energetically demanding, responses to and recovery from atrazine exposures may subsequently impact growth, development, and reproduction.
