Mechanisms of high-voltage immunity in the electric eel

• Applicant: Professor Dr. Stefan Schuster, since 4/2022
• Subject Area: Animal Physiology and Biochemistry ; Sensory and Behavioural Biology
• Term: since 2021
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 493831595

Electric eels are renowned for their capacity to generate high-voltage electric shocks that immediately paralyze prey and foes. However, up to know it is still puzzling whether and how electric eels are protected from electrocuting themselves. In this project, we will first examine the degree to which electrically vulnerable organs such as the nervous system, the heart or the skeletal muscles are protected in vivo. To achieve this, we will examine the effects of self-produced and controlled external electric shocks of various strengths and spectral composition: We will monitor the effect on specific behaviors and on the eel's electrocardiogram, which – as we have shown – can be picked up noninvasively using a suitably constructed amplifier. Subsequently, and guided by the in vivo findings, we will explore the flow of potentially detrimental electrical currents within the body of the eel. We will directly measure how alternating currents of different amplitude and frequency flow through various organs of the electric eel. The biophysical properties of tissues that strongly affect current flow will then be quantitatively characterized. In the final phase we will remove specific organs from the fish`s body so that they lose protection from potentially shielding environments. We will dissect out the electric eel’s heart, nerves, and skeletal muscles, keep them alive via perfusion with oxygenated saline solution and examine their sensitivity to electric shocks ex vivo. These experiments will directly show whether some of the potentially electrovulnerable organs of the electric eel have an intrinsically higher tolerance to electric currents. In summary, our project will for the first time provide insights into the mechanisms that protect the electric eel against high-voltage discharges.

• DFG Programme: Research Grants
• Ehemaliger Antragsteller: Dr. Georg Welzel, until 4/2022