Anesthetic effects of a three-drugs mixture —comparison of administrative routes and antagonistic effects of atipamezole in mice—

Abstract

The anesthetic mixture of medetomidine (MED), midazolam (MID) and butorphanol (BUT) produced anesthetic duration of around 40 minutes (min) in ICR mice. We reported that this anesthetic mixture produced almost the same anesthetic effects in both male and female BALB/c and C57BL/6J strains. Intraperitoneal (IP) administration of drugs has been widely used in mice. However, various injectable routes of the anesthetic mixture may cause different anesthetic effects. First, we examined effects of the anesthetic mixture by subcutaneous (SC) and intravenous (IV) injection compared to IP injection. After injection of the anesthetic mixture, administration of atipamezole (ATI) induced mice recovery from anesthesia. Secondly, we examined how different dosage and optimum injection timing of ATI affected mice recovery from anesthesia. We used an anesthetic score to measure anesthetic duration and a pulse oximeter to monitor vital signs under anesthesia. Usually, drugs from SC injection work more weakly than IP or IV injection. However, we found no significant differences of anesthetic duration among the three different injection routes. Antagonistic effects of ATI (0.3 mg/kg and 1.5 mg/kg) worked equally when administered at 30 min after injection of the anesthetic mixture. Antagonistic effects of ATI (1.5 mg/kg) were stronger than ATI (0.3 mg/kg) at 10 min after injection of the anesthetic mixture. The anesthetic mixture is a useful drug to induce nearly the same anesthetic effects by different injection routes and has an antagonist of ATI which helps mice quickly recover from anesthesia. These results may contribute to the welfare of laboratory animals.

Influence of Mechanical Force on Bone Matrix Proteins in Ovariectomised Mice and Osteoblast-like MC3T3-E1 Cells

“…After an acclimation period of 1 week, the mice were subjected to bilateral ovariectomy (OVX) or a sham operation via a dorsolateral incision after intraperitoneal administration of a combination anaesthetic [medetomidine hydrochloride, 0.3 mg/kg (Domitol; Nippon Zenyaku Kogyo Co., Ltd., Fukushima, Japan); midazolam, 4.0 mg/kg (Sandoz; Sandoz K.K. Tokyo, Japan) and butorphanol, 5.0 mg/kg (Vetorphale; Meiji Seika Pharma Co., Ltd., Tokyo, Japan)] (20,21). For OVX, the ovaries were excised, oviducts were put back in their original position and the incisions were closed.…”

Comparison of the anesthetic effect by the injection route of mixed anesthesia (medetomidine, midazolam and butorphanol) and the effect of this anesthetic agent on the respiratory function

“…In recent years, the general anesthetic consisting of the combination of medetomidine, midazolam and butorphanol (MMB) has been used in Japan [8]. The use of an injectable agent for inducing general anesthesia entails difficulty in controlling the anesthetic depth and duration, but MMB anesthesia has the advantage that its effects can be rapidly reversed by the injection of atipamezole [10,11,[13][14][15]. Use of MMB for inducing general anesthesia has not become widespread in other countries, where ketamine/xylazine and isoflurane are commonly applied; therefore, experimental data regarding MMB anesthesia are still limited.…”

Injection anaesthesia with fentanyl–midazolam–medetomidine in adult female mice: importance of antagonization and perioperative care

“…In addition, the potential for drugs used for anaesthesia to interfere with experimental procedures and results can play a role when choosing an appropriate anaesthetic regime (4,5) . Additionally, problems of availability, particularly in drugs regulated under narcotic laws in many countries, can determine whether specific substances are applied or not (1)(2)(3) .…”