Memory-impairing effects of local anesthetics in an elevated plus-maze test in mice.
Post-training intracerebroventricular administration of procaine (20 micrograms/microliter) and dimethocaine (10 or 20 micrograms/microliter), local anesthetics of the ester class, prolonged the latency (s) in the retention test of male and female 3-month-old Swiss albino mice (25-35 g body weight; N = 140) in the elevated plus-maze (mean +/- SEM for 10 male mice: control = 41.2 +/- 8.1; procaine = 78.5 +/- 10.3; 10 micrograms/microliter dimethocaine = 58.7 +/- 12.3; 20 micrograms/microliter dimethocaine = 109.6 +/- 5.73; for 10 female mice: control = 34.8 +/- 5.8; procaine = 55.3 +/- 13.4; 10 micrograms/microliter dimethocaine = 59.9 +/- 12.3 and 20 micrograms/microliter dimethocaine = 61.3 +/- 11.1). However, lidocaine (10 or 20 micrograms/microliter), an amide class type of local anesthetic, failed to influence this parameter. Local anesthetics at the dose range used did not affect the motor coordination of mice exposed to the rota-rod test. These results suggest that procaine and dimethocaine impair some memory process(es) in the plus-maze test. These findings are interpreted in terms of non-anesthetic mechanisms of action of these drugs on memory impairment and also confirm the validity of the elevated plus-maze for the evaluation of drugs affecting learning and memory in mice.
Departamento de Farmacologia, Universidade Federal de Santa Catarina, Florianópolis, Brasil.
S L
SL
Blatt
R N
RN
Takahashi
D000704:Analysis of Variance; D000779:Anesthetics, Local / Q000494:pharmacology*; D000818:Animals; D005260:Female; D008012:Lidocaine / Q000008:administration & dosage / Q000494:pharmacology; D008297:Male; D018782:Maze Learning / Q000187:drug effects*; D008568:Memory / Q000187:drug effects*; D051379:Mice; D011343:Procaine / Q000008:administration & dosage / Q000494:pharmacology; D011412:Propanolamines / Q000008:administration & dosage / Q000494:pharmacology; D011930:Reaction Time; D013997:Time Factors
D000779:Anesthetics, Local; D011412:Propanolamines; D011343:Procaine; D008012:Lidocaine