Mouse and Rat Anesthesia and Analgesia

Abstract

Anesthesia and analgesia play pivotal roles in ethically and humanely using animal models in research, especially concerning mice and rats. These rodent species, extensively utilized in scientific investigations due to their genetic resemblance to humans, serve as invaluable tools for studying diseases and testing treatments. Proper anesthesia and analgesia not only prioritize animal welfare but also heighten experimental validity by minimizing stress‐induced physiological responses. Recent years have seen remarkable advancements in anesthesia for mice and rats. The focus has shifted away from the ‘one size fits all’ toward tailoring anesthesia protocols, considering factors like age, strain, and the nature of the experimental procedure. The use of inhalation agents such as isoflurane and sevoflurane is often preferred due to their rapid induction and recovery characteristics, allowing precise control over anesthesia depth. However, refinements in injectable anesthetic agents also provide researchers the flexibility to select suitable agents based on study requirements. Additionally, progress in analgesic techniques has led to effective pain management strategies for these rodents. Common analgesics such as nonsteroidal anti‐inflammatory drugs (NSAIDs), opioids, and local anesthetics are administered to alleviate pain and discomfort. However, standard practice also involves continuous monitoring of animals' behavior and physiological parameters, ensuring timely adjustments in analgesic regimens for optimal pain relief without compromising experimental outcomes. By integrating tailored anesthesia and analgesia protocols into the experimental design, researchers uphold high animal welfare standards while obtaining reliable scientific data. This contributes significantly to advancing medical knowledge and therapeutic interventions with reproducible results. Published 2024. This article is a U.S. Government work and is in the public domain in the USA. Current Protocols published by Wiley Periodicals LLC.Basic Protocol 1: Injectable anesthesia for mouse and ratBasic Protocol 2: Inhalant anesthesia using isoflurane for mouse and ratBasic Protocol 3: Analgesia for mice and rats

Lumbar Intrathecal Injection in Adult and Neonatal Mice

“…During cleansing ensure that water is released undisturbed with no gradient towards any direction. (Oh & Narver, 2024), as described in Basic Protocol 1. Check the depth of anesthesia by firmly pinching the paws using atraumatic forceps.…”

“…Evaluation includes tissue isolation, embedding in optimal cutting temperature (OCT), cryosectioning and examination of EGFP autofluorescence under the microscope (Paletzki & Gerfen, 2019). (Oh & Narver, 2024), as described in Basic Protocol 1. Check the depth of anesthesia by firmly pinching the paws using atraumatic forceps.…”

“…Animals injected with an AAV9 vector ubiquitously expressing EGFP are evaluated 6 weeks after injection for their vector genome copy numbers (VGCN) in the tissues of interest. (Oh & Narver, 2024), as described in Basic Protocol 1. Check the depth of anesthesia by firmly pinching the paws using atraumatic forceps.…”

“…2. Anesthetize one mouse at a time using an insulin syringe for intraperitoneal injection of ketamine/xylazine solution (ketamine 80 to 100 mg/kg, xylazine 10 to 12.5 mg/kg) or any other compatible anesthesia method (Oh & Narver, 2024). Check the depth of anesthesia by firmly pinching the paws using atraumatic forceps.…”