Mechanisms of anoxia tolerance in non-excitable cells: investigating the role of the mitochondria in Western Painted Turtle hepatocytes
Year: 2018
Type: dissertation
Abstract: Organisms like the Western Painted Turtle (Chrysemys picta), which overwinter in ice-covered ponds, can survive long periods of limited oxygen availability by dramatically reducing their metabolic rate. Cellular mechanisms underlying this adaptation have predominantly been studied in brain tissue - excitable cells. This study aims to investigate the role of mitochondria in the anoxia tolerance of C. picta hepatocytes, non-excitable cells. Using the membrane potential sensitive compound Rhodamine-123, mitochondrial membrane potential depolarized in anoxic hepatocytes, just as in brain. Furthermore, pharmacological activation of mitochondrial ATP-sensitive potassium channels (mKATPs) simulated the anoxic response, while inhibition of mKATPs under anoxic conditions abolished the anoxic response, suggesting that mKATPs are important in the maintenance of mitochondrial membrane potential and subsequent changes during anoxia in both cell types. Hepatocytes differ in their calcium response, as calcium imaging using Oregon Green found no change in intracellular calcium levels under anoxia.
Source: TSpace (University of Toronto)
Author: Farah Al-Dajani
Language: English
Subfield: Ecology
Field: Environmental Science
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W3133970717