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bioRxiv · 10.1101/2020.08.28.266890

Preconditioning of Caenorhabditis elegans to Anoxic Insult by Inactivation of Cholinergic, GABAergic, and Muscle Activity

Abstract

For most metazoans, oxygen deprivation leads to cell dysfunction and if severe, death. Sublethal stress prior to a hypoxic or anoxic insult ("preconditioning") can protect cells from subsequent oxygen deprivation. The molecular mechanisms by which sublethal stress can buffer against a subsequent toxic insult and the role of the nervous system in the response are not well understood. We studied the role of neuronal activity preconditioning to oxygen deprivation in C. elegans. Animals expressing the histamine gated chloride channels (HisCl1) in select cell populations were used to temporally and spatially inactivate the nervous system or tissue prior to an anoxic insult. We find that inactivation of the nervous system for 3 hours prior to the insult confers resistance to a 48-hour anoxic insult in 4th-stage larval animals. Experiments show that this resistance can be attributed to loss of activity in cholinergic and GABAergic neurons as well as in body wall muscles. These observations indicate that the nervous system activity can mediate the organisms response to anoxia.

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Bennett, H. L., McClanahan, P. D., Fang-Yen, C., Kalb, R. G.. 2020-08-30. Preconditioning of Caenorhabditis elegans to Anoxic Insult by Inactivation of Cholinergic, GABAergic, and Muscle Activity. https://doi.org/10.1101/2020.08.28.266890

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