Brain dysfunction during warming is linked to oxygen limitation in larval zebrafish

• DOI: 10.1073/pnas.2207052119
• Publication Date: 2022-09-19T19:16:45Z
• Authors: Anna H. Andreassen; Petter Hall; Pouya Khatibzadeh; Fredrik Jutfelt; Florence Kermen
• Keywords: Danio; Limiting; Calcium imaging

Understanding the physiological mechanisms that limit animal thermal tolerance is crucial in predicting how animals will respond to increasingly severe heat waves. Despite their importance for understanding climate change impacts, these underlying upper limits of are largely unknown. It has been hypothesized fish limited by brain and ultimately caused a global depolarization. In this study, we developed methods measuring (CT max ) larval zebrafish ( Danio rerio with simultaneous recordings activity using GCaMP6s calcium imaging both free-swimming agar-embedded fish. We discovered during warming, CT precedes, therefore not by, Instead, coincides decline spontaneous neural loss response visual stimuli. By manipulating water oxygen levels up down, found availability heating affects locomotor-related activity, stimuli, . Our results suggest mechanism limiting larvae insufficient causing impaired function.