Mm. Metzger et Dc. Riccio, DIFFERENTIAL-EFFECTS OF KETASET ROMPUN ANESTHESIA ON HYPOTHERMIA-INDUCED RETROGRADE-AMNESIA AND ITS RECOVERY/, Neurobiology of learning and memory, 64(3), 1995, pp. 245-256
A nonbarbiturate anesthetic consisting of ketamine HCl (Ketaset) and x
lyazine (Rompun) was administered to assess the effects of anesthesia
on hypothermia-induced retrograde amnesia in Long Evans hooded and Spr
ague-Dawley albino rats. Results from Experiment la indicate that this
anesthetic does not attenuate retrograde amnesia, and the findings fr
om Experiment 1b suggest that awakening from Ketaset/Rompun anesthesia
at normal body temperature (following administration of deep body coo
ling) does not attenuate the resulting hypothermia-induced retrograde
amnesia. Experiment 2 demonstrated that various delays between trainin
g and hypothermia resulted in a temporal gradient that was the same fo
r animals cooled while either conscious or under anesthesia. The resul
ts of Experiment 3 showed that rats made amnesic while under anesthesi
a did not recover the target memory if given a recooling treatment, bu
t rats that were made amnesic while conscious did recover the memory w
ith the same reminder treatment. These findings indicate that the cons
cious processing of stimuli associated with hypothermia treatment is n
ot necessary in inducing hypothermia-induced retrograde amnesia, but t
hat conscious processing is an important factor if the amnesia is to b
e recovered with a recooling treatment. (C) 1995 Academic Press, Inc.