Linalool acts as a fast and reversible anesthetic in Hydra

Autoři: Tapan Goel aff001;  Rui Wang aff002;  Sara Martin aff002;  Elizabeth Lanphear aff002;  Eva-Maria S. Collins aff001
Působiště autorů: Department of Physics, University of California San Diego, La Jolla, CA, United States of America aff001;  Department of Biology, Swarthmore College, Swarthmore, PA, United States of America aff002;  Department of Bioengineering, University of California San Diego, La Jolla, CA, United States of America aff003
Vyšlo v časopise: PLoS ONE 14(10)
Kategorie: Research Article


The ability to make transgenic Hydra lines has allowed for quantitative in vivo studies of Hydra regeneration and physiology. These studies commonly include excision, grafting and transplantation experiments along with high-resolution imaging of live animals, which can be challenging due to the animal’s response to touch and light stimuli. While various anesthetics have been used in Hydra studies, they tend to be toxic over the course of a few hours or their long-term effects on animal health are unknown. Here, we show that the monoterpenoid alcohol linalool is a useful anesthetic for Hydra. Linalool is easy to use, non-toxic, fast acting, and reversible. It has no detectable long-term effects on cell viability or cell proliferation. We demonstrate that the same animal can be immobilized in linalool multiple times at intervals of several hours for repeated imaging over 2–3 days. This uniquely allows for in vivo imaging of dynamic processes such as head regeneration. We directly compare linalool to currently used anesthetics and show its superior performance. Linalool will be a useful tool for tissue manipulation and imaging in Hydra research in both research and teaching contexts.

Klíčová slova:

Anesthesia – Anesthetics – Fluorescence imaging – In vivo imaging – Neurons – Hydra – Urethanes – Head regeneration


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