Mice have long been a preferred species for biomedical research animal models due to their anatomical, physiological, and genetic similarity to humans. The advantages of using mice in laboratory research include their small size, ease of maintenance, short life cycle, and abundant genetic resources.1 Laboratory rats and mice provide ideal animal models for biomedical research and comparative medicine studies because they have many similarities to humans in terms of anatomy and physiology. Likewise, rats, mice, and humans each have approximately 30,000 genes of which approximately 95% are shared by all three species.2 Whether formulating cancer drugs or testing dietary supplements, mice play a critical role in developing new medical breakthroughs. According to the Foundation for Biomedical Research (FBR) 95% of all lab animals are mice and rats.3

Scientists and researchers rely on mice in particular for several reasons:

• Mice are small, easily housed and maintained, and adapt well to new surroundings. 

• Mice reproduce quickly and have a short lifespan (two to three years).

• Mice are relatively inexpensive and can be bought in large quantities from commercial producers that breed rodents specifically for research. 

• Mice are mild-tempered and docile, making them easy for researchers to handle.

The aforementioned commercial producers have standardized thousands of specialized mouse strains over the years, as well as tailoring strains for specific researchers and research applications. In fact, most of the mice and rats used in medical trials are inbred so that, other than sex differences, they are almost identical genetically.2 This helps to make the results of medical trials more uniform, which is particularly important in the case of drug development.

Anesthesia protocols influence the survival of laboratory animals and can also greatly affect the experimental data results. Thus, effective and reliable anesthetic protocols and medications are essential in experimental studies on animal models, since the data derived can profoundly affect the outcome of trials. 

KAX Injectable for Mice 

KAX Injectable Anesthesia (Ketamine 6.06 mg/ml / Acepromazine 0.6mg/ml / Xylazine 0.667mg/ml) was formulated by NexGen Pharmaceuticals specifically for use in the sedation of mice in the laboratory setting. 

Ketamine

Ketamine is a dissociative general anesthetic and NMDA-Receptor Antagonist that is used to induce loss of consciousness, or anesthesia. It can produce relaxation and relieve pain in humans and animals. A Class III scheduled drug, it is approved for use in hospitals and other medical settings as an anesthetic. Other drugs in this category include the hallucinogen, phencyclidine (PCP), dextromethorphan (DXM), and nitrous oxide (laughing gas).4

Ketamine is most often used in veterinary medicine. In humans, it can induce and maintain general anesthesia before, during, and after surgery. For medical purposes, ketamine is either injected into a muscle or given through an intravenous (IV) line. It is considered safe as an anesthetic, because it does not reduce blood pressure or lower the breathing rate. However, it is also a commonly abused “recreational” drug, due to its hallucinogenic, tranquilizing and dissociative effects.

Acepromazine

Acepromazine is a phenothiazine tranquilizer that blocks dopamine receptors in the CNS and depresses the reticular-activating system, resulting in sedation. Acepromazine also blocks α-adrenergic receptors. Acepromazine is not an analgesic, but potentiates the effects of analgesic drugs, most notably, opioids.4 Acepromazine is metabolized by the liver and eliminated by the kidneys and as a result has a longer half-life in young animals.4 The duration of effect in adult animals is typically 4 to 8 hours and would reasonably have a longer duration of action in neonates and juveniles.

Acepromazine causes sedation without significant respiratory depression. Although systemic blood pressure can be reduced as a result of vasodilation, acepromazine administration can also result in vagally-induced bradycardia.4 Caution should be used when administering acepromazine to animals that are predisposed to seizures or with a seizure history because it can lower the seizure threshold. The consequences of this effect remain speculative. The dose of acepromazine should be decreased in neonates or those animals with hepatic insufficiency caused by its slower metabolism and potentially long duration.1 Acepromazine is considered to be a safe and effective tranquilizer in juvenile animals.

Xylazine

Xylazine HCl is a non-narcotic drug used in veterinary medicine as a sedative with analgesic and muscle relaxant properties. It is used on many different animal species such as cattle, sheep, horses, dogs, cats, deer, rats, and elk to calm and facilitate handling, perform diagnostic and surgical procedures, relieve pain, or act as a local anesthetic.4

Xylazine is approved by the U.S. Food and Drug Administration (FDA) for veterinary use only. Typically, this drug is administered either alone or in conjunction with other anesthetics (e.g., ketamine or barbiturates) intravenously, intramuscularly, or orally for sedative and relaxant properties.3 Xylazine typically has an onset of effects within a few minutes and lasts up to four hours in animals.

Where to buy KAX Injectable Anesthesia

KAX Injectable is available in the U.S. only through NexGen Pharmaceuticals. KAX Injectable (Ketamine 6.06 mg/ml / Acepromazine 0.6mg/ml / Xylazine 0.667mg/ml) by NexGen provides superior relaxation and recovery times when used for mouse sedation and other veterinary anesthesia applications involving small animals.

FOR RX ONLY: A valid prescription from a licensed veterinarian is required for dispensing this medication.

1Bryda, E. The Mighty Mouse: The Impact of Rodents on Advances in Biomedical Research. Missouri Medical Journal, 2013 May-Jun; 110(3): 207–211.

2Suckow, M., et. al. The Laboratory Mouse, Laboratory Animal Pocket Reference Series (Boca Raton: CRC Press, 2001)

3Cicero, Luca et al. Anesthesia protocols in laboratory animals used for scientific purposes. Acta bio-medica : Atenei Parmensis vol. 89,3 337-342. 8 Oct. 2018.

4Plumb’s Veterinary Drugs.