Lasting effects of ketamine and isoflurane administration on anxiety- and panic-like behavioral responses in Wistar rats.

Ketamine (80 mg/kg) produced anxiogenic effects in male rats two and seven days after administration in the elevated T-maze test, while both 40 and 80 mg/kg doses decreased panic-like behavior. In the light/dark test, ketamine was anxiogenic. Isoflurane did not alter behavior in the elevated T-maze but reduced exploration of the open field center after seven days. Neither anesthetic caused oxidative liver damage. Ketamine reduced cellular metabolism and led to neuronal death in amygdalar primary cell cultures. The authors conclude that ketamine and isoflurane induce pronounced long-lasting anxiety-related behaviors in male rats.

Study at a glance

Abstract

In clinical and laboratory practice, the use of anesthetics is essential in order to perform surgeries. Anesthetics, besides causing sedation and muscle relaxation, promote several physiological outcomes, such as psychotomimetic alterations, increased heart rate, and blood pressure. However, studies depicting the behavioral effect induced by ketamine and isoflurane are conflicting. In the present study, we assessed the behavioral effects precipitated by ketamine and isoflurane administration. We have also evaluated the ketamine effect on cell cytotoxicity and viability in an amygdalar neuronal primary cell culture. Ketamine (80 mg/kg) caused an anxiogenic effect in rats exposed to the elevated T-maze test (ETM) 2 and 7 days after ketamine administration. Ketamine (40 and 80 mg/kg) administration also decreased panic-like behavior in the ETM. In the light/dark test, ketamine had an anxiogenic effect. Isoflurane did not change animal behavior on the ETM. Neither ketamine nor isoflurane changed the spontaneous locomotor activity in the open field test. However, isoflurane-treated animals explored less frequently the OF central area seven days after treatment. Neither anesthetic caused oxidative damage in the liver. Ketamine also reduced cellular metabolism and led to neuronal death in amygdalar primary cell cultures. Thus, our work provides evidence that ketamine and isoflurane induce pronounced long lasting anxiety-related behaviors in male rats.