Related Experiment Video
Updated: May 12, 2026
Assessing Changes in Volatile General Anesthetic Sensitivity of Mice after Local or Systemic Pharmacological Intervention
Published on: October 17, 2013
Evaluation of anesthetic effects of remimazolam using mouse model with jugular vein cannulation
Aoi Ikuse-Oshio1, Yuki Azetsu2, Aiko Hirayama1
1Department of Pharmacology, Graduate School of Dentistry, Showa Medical University, 1-5-8 Hatanodai, Shinagawa, Tokyo, 142-8555, Japan; Department of Anesthesiology, Graduate School of Dentistry, Showa Medical University, 2-1-1 Kitasenzoku, Ota, Tokyo, 145-8515, Japan.
Objective:
Remimazolam, a novel ultra-short-acting benzodiazepine anesthetic, provides rapid recovery with minimal circulatory depression, making it a promising agent for procedural sedation. However, differences in regulatory approvals and safety requirements across countries limit its clinical use. Therefore, its pharmacological properties and safety should be clarified in further studies. In this study, jugular vein-cannulated model mice were administered intravenous anesthetic, and the sedative effects of remimazolam were compared with those of midazolam and propofol.
Methods:
Following jugular vein cannulation, each mouse was administered a single intravenous dose of remimazolam or midazolam, and changes in sedation levels were assessed using a sedation scale. In another test, continuous infusion of propofol or remimazolam was administered using a precise microflow pump and sedation scale scores, defensive reflexes, and vital signs were analyzed.
Results:
The sedation scale score increased after a single administration of remimazolam or midazolam in a concentration-dependent manner, followed by gradual recovery, whereas continuous administration caused a gradual increase that stabilized over time. Continuous remimazolam administration (30 mg/kg/h) produced sedation comparable to that produced by propofol administration (120 mg/kg/h), although with much smaller decreases in heart and breathing rates. Defensive reflex reactivity in mice administered remimazolam exhibited a shorter time to reflex extinction than in those administered propofol, with repeated extinction and recovery cycles.
Conclusions:
Our findings suggest that the jugular vein-cannulated mouse model is useful for evaluating time-dependent sedative effects. Continuous remimazolam administrationmaintained stable sedation with minimal vital depression and faster defensive reflex suppression than propofol administration.
Insights
Remimazolam provides effective procedural sedation with rapid recovery and minimal vital sign depression compared to propofol. This ultra-short-acting anesthetic demonstrates faster defensive reflex suppression in a mouse model.
Area of Science:
- Pharmacology
- Anesthesiology
- Preclinical Research
Background:
- Remimazolam is a novel ultra-short-acting benzodiazepine anesthetic with rapid recovery and minimal circulatory depression, suitable for procedural sedation.
- Global regulatory differences and safety concerns necessitate further studies on remimazolam's pharmacological properties and safety profile.
Purpose of the Study:
- To compare the sedative effects of remimazolam with midazolam and propofol in a jugular vein-cannulated mouse model.
- To evaluate the time-dependent sedative effects and safety of remimazolam during continuous infusion.
Main Methods:
- Jugular vein-cannulated mice received single intravenous doses of remimazolam or midazolam, with sedation assessed using a sedation scale.
- Continuous infusion of remimazolam or propofol was administered, analyzing sedation scores, defensive reflexes, and vital signs.
Main Results:
- Both remimazolam and midazolam showed concentration-dependent sedation after single administration, with gradual recovery.
- Continuous remimazolam infusion (30 mg/kg/h) achieved sedation comparable to propofol (120 mg/kg/h) with less vital sign depression.
- Remimazolam demonstrated faster defensive reflex suppression and recovery cycles than propofol.
Conclusions:
- The jugular vein-cannulated mouse model effectively evaluates time-dependent sedative effects.
- Continuous remimazolam administration ensures stable sedation with minimal vital depression and superior defensive reflex suppression compared to propofol.
