Hydra is composed of only a small number of cell types originating from three (ectodermal, endodermal and interstitial) stem cell lineages. It consists of a hollow cylindrical body column with a head on one end, consisting of a ring of tentacles and a dome-shaped hypostome, and an adhesive basal disk on the other end. Hydra is an optically transparent polyp a few millimeters in length. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.Ĭompeting interests: The authors have declared that no competing interests exist.Ībraham Trembley’s careful and systematic studies on Hydra regeneration, published in his Memoires in 1744, brought this freshwater cnidarian into the spotlight of biological research. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.ĭata Availability: All relevant data are within the manuscript and its Supporting Information files.įunding: The National Science Foundation (grant number CMMI-1463572), the Research Corporation for Science Advancement, and the Gordon and Betty Moore foundation, awarded to EMSC. Received: ApAccepted: OctoPublished: October 24, 2019Ĭopyright: © 2019 Goel et al. Gilestro, Imperial College London, UNITED KINGDOM Linalool will be a useful tool for tissue manipulation and imaging in Hydra research in both research and teaching contexts.Ĭitation: Goel T, Wang R, Martin S, Lanphear E, Collins E-MS (2019) Linalool acts as a fast and reversible anesthetic in Hydra. We directly compare linalool to currently used anesthetics and show its superior performance. This uniquely allows for in vivo imaging of dynamic processes such as head regeneration. 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. It has no detectable long-term effects on cell viability or cell proliferation. Linalool is easy to use, non-toxic, fast acting, and reversible. Here, we show that the monoterpenoid alcohol linalool is a useful anesthetic for Hydra. 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. 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. The ability to make transgenic Hydra lines has allowed for quantitative in vivo studies of Hydra regeneration and physiology.

Hydra animal