Date of Degree Completion
Master of Science (MS)
Second Committee Member
Third Committee Member
Freeze Tolerance is an adaptation seen amongst several species of amphibians as a way of surviving during wintering months. Use of cryoprotectants is seen in all freeze tolerant species (glucose/glycerol). Synthesis and transportation mechanisms that regulate this process are not yet fully understood. Arginine vasotocin is a neurohypophyseal peptide known to have glycogenolytic effects as well as regulate several key processes involved in fluid and solute transportation. Although one prior study suggested that AVT is not involved in responses to freezing, I measured AVT levels during freezing and injected an AVT antagonist to see if it would affect the production of cryoprotectants within liver and thigh muscle during freezing. There was a dramatic increase in systemic AVT levels (p=0.05) during freezing by Pseudacris regilla. The AVT antagonist caused a dramatic reduction (~50%) in hepatic glucose and glycerol concentrations. These results demonstrate that AVT is involved with the process of cryoprotectant sourcing during freezing events in Pseudacris regilla.
Ingels, Ben, "The Effect of Arginine Vasotocin on Cryoprotectant Production during Freezing in the Pacific Chorus Frog, Pseudacris Regilla" (2017). All Master's Theses. 599.