Ketamine Inhalation Alters Behavior and Lower Urinary Tract Function in Mice.

Area of Science:

• Toxicology
• Neuroscience
• Urology

Background:

• Ketamine abuse is a growing public health concern.
• Existing animal models for ketamine abuse primarily use injections.
• A novel ketamine inhalation model is needed to mimic human abuse patterns.

Purpose of the Study:

• To evaluate behavioral and lower urinary tract changes in mice using a novel ketamine inhalation model.
• To compare these changes to those induced by ketamine intraperitoneal injection.
• To establish ketamine inhalation as a viable model for studying ketamine abuse.

Main Methods:

• C57BL/6N mice were exposed to ketamine or saline fog via ultrasonic nebulizer twice weekly for three months (inhalation group).
• A separate group received ketamine or saline intraperitoneal injections twice weekly for three months (injection group).
• Behavioral changes (locomotor activity, jumping) and lower urinary tract function (urine spots, cystometry, histology) were assessed.

Main Results:

• Both ketamine inhalation (KI) and intraperitoneal injection (KP) groups showed increased center crossing and distance traveled compared to controls (SI and SP).
• KI mice exhibited unique behaviors like popcorn-like jumping.
• Both KI and KP groups displayed detrusor overactivity, reduced bladder capacity, and mucosal damage.

Conclusions:

• Ketamine inhalation induces comparable behavioral and lower urinary tract changes to ketamine injections in mice.
• The novel ketamine inhalation model effectively mimics aspects of human ketamine abuse.
• This model provides a valuable tool for further research into the effects of ketamine abuse.