Acquisition and
Retrieval of Conditioned Taste Aversion is
Impaired by Brain Damage Caused by Two Hours of
Pilocarpine-Induced Status Epilepticus
J. ŠROUBEK1,
J. HORT1, V. KOMÁREK2, M.
LANGMEIER3, G. BROŽEK4,5
1Department
of Neurology. Second Faculty of Medicine, Charles
University, Pediatric 2Neurology
and 4Physiology,
First Faculty of Medicine, 3Department
of Physiology and 5Institute
of Physiology, Academy of Sciences of the Czech
Republic, Prague, Czech Republic
Received
October 2, 2000
Accepted March 15, 2001
Summary
The
effect of Cavalheiro's pilocarpine model of
epileptogenesis upon conditioned taste aversion
(CTA), an important example of nondeclarative
memory, was studied in adult Long Evans rats.
Deterioration of CTA was studied during the
silent period between pilocarpine-induced status
epilepticus (SE) and delayed spontaneous
recurrent seizures. SE was elicited by i.p.
injection of pilocarpine (320 mg/kg ) and
interrupted after 2 hours by clonazepame (1 mg/kg
i.p.). Peripheral cholinergic symptoms were
suppressed by methylscopolamine (1 mg/kg i.p.),
administered together with pilocarpine. CTA was
formed against the salty taste of isotonic LiCl.
In the experiment of CTA acquisition, the CTA was
formed and tested during the silent period after
SE. In the experiment of CTA retrieval, the CTA
was acquired before SE and the retrieval itself
was tested during the silent period. Retrieval of
CTA acquired before SE was impaired more than the
retrieval of CTA formed during the silent period.
Our findings indicate that epileptic seizures can
disrupt even non-declarative memory but that CTA
formed by the damaged brain can use its better
preserved parts for memory trace formation.
Ketamine (50 mg/kg i.p.) applied 2 min after the
onset of pilocarpine-induced status epilepticus
protected memory deterioration.
.
Key words
Conditioned
taste aversion · Epilepsy · Pilocarpine · Nondeclarative memory
Reprint
requests
Prof.
G. Brožek, M.D., Department of Physiology,
Second Faculty of Medicine, Charles University,
Plzenska 221/130, 150 00 Prague 5, Czech
Republic. Fax + 420 2 57210995, e-mail: gustav.brozek@lfmotol.cuni.cz
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