Linalool acts as a fast and reversible anesthetic in Hydra

PLoS One. 2019 Oct 24;14(10):e0224221. doi: 10.1371/journal.pone.0224221. eCollection 2019.

Abstract

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.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Acyclic Monoterpenes / pharmacology*
  • Anesthetics / pharmacology*
  • Animals
  • Animals, Genetically Modified / physiology*
  • Head / growth & development*
  • Hydra / drug effects
  • Hydra / physiology*
  • Insecticides / pharmacology
  • Regeneration / drug effects
  • Regeneration / physiology*

Substances

  • Acyclic Monoterpenes
  • Anesthetics
  • Insecticides
  • linalool

Grants and funding

The National Science Foundation (grant number CMMI-1463572), the Research Corporation for Science Advancement, and the Gordon and Betty Moore foundation, awarded to EMSC. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.