Faculty Mentor(s)
Dr. Erika Calvo-Ochoa, Biology and Neuroscience
Document Type
Poster
Event Date
4-12-2024
Abstract
Hypoxia, i.e. low oxygen, is a physiologically damaging condition found in many health conditions such as ischemic stroke, sleep apnea, asthma, etc. Additionally, decreased dissolved oxygen levels in aquatic environments occur as a result of climate change. Zebrafish offer an excellent model to study hypoxia due to extensive neuroplasticity and injury-induced cell proliferation, which allows them to recover lost function in the central nervous system (CNS). We have shown that olfaction (i.e., the ability to smell), decreases in response to hypoxic exposure in adult zebrafish. Thus, it is important to study the structural abnormalities underlying this loss of smell. Olfactory sensory neurons (OSN) in the olfactory epithelium (OE) detect and transmit odorant information to the olfactory bulb (OB) which discriminates odorants and relays the information further to the brain. We hypothesized that hypoxia is associated with a loss of smell due to abnormalities in the olfactory epithelium, specifically in the form of damage to OSNs and mucus production. To do this, we exposed adult zebrafish to acute hypoxia (0.6-0.8 mg/mL dissolved oxygen) for 15 minutes. OSN activity was analyzed through immunohistochemistry using c-Fos, a marker of neural activity, following exposure to the odorants, cadaverine and food essence, and compared between conditions. Additionally, to assess whether the loss of olfactory function was due to dysfunction in mucus production, we utilized Alcian Blue stainings of the OE to visualize the mucus layer and the presence of mucus-producing Bowman Glands. We predicted that hypoxic conditions would show a decreased activity of OSNs in the following odorant exposure. Additionally, because the mucus layer has been shown to thin in response to hypoxia, we predict that there will be more Bowman Glands to counteract the mucus reduction. This work provides insights into hypoxia’s impact on olfaction, specifically olfactory morphology and function.
Recommended Citation
Repository citation: Yakes, Madelyn; DeWitt, Skylar; and Hill, Gracie, "Fishing for Answers: Studying Hypoxia's Effects on the Zebrafish Olfactory Epithelium" (2024). 23rd Annual A. Paul and Carol C. Schaap Celebration of Undergraduate Research and Creative Activity (2024). Paper 92.
https://digitalcommons.hope.edu/curca_23/92
April 12, 2024. Copyright © 2024 Hope College, Holland, Michigan.
Comments
This research was supported by Hope College’s Neuroscience program and Biology Department, and in part by funding provided by the National Aeronautics and Space Administration (NASA), under award number 80NSSC20M0124, Michigan Space Grant Consortium (MSGC).