Abstract:
Objective: We compared the effects of 2 sedative drugs, dexmedetomidine and midazolam, on motor
performance and analgesic efficacy in a rat model.
Materials and methods: Rats were randomly divided into the following 4 groups on the basis of the
treatment received. The first group received 83 mg/kg/min midazolam; the second, 1 mg/kg/min
dexmedetomidine; the third, 83 mg/kg/min morphine; and the fourth was a control group. The rats
were measured motor coordination and pain reflexes by using rotarod, accelerod, hot plate, and tail
flick tests.
Results: At all the tested speeds, the midazolam-injected rats remained on the rotarod longer than did
the dexmedetomidine-injected rats. Furthermore, in the 10-minute accelerod test, the midazolaminjected
rats remained for a longer duration than did the dexmedetomidine-injected rats. The latency
time for the hot plate test was significantly higher at 10 minutes and 20 minutes in the dexmedetomidine
group than in the midazolam group. Further, the latency time at 10 minutes for the tail flick test
was greater in the dexmedetomidine group than in the midazolam group.
Conclusions: In this rat model, midazolam results in faster recovery of motor coordination performance
when compared with dexmedetomidine.
