Chronic methylphenidate-effects over circadian cycle of young and adult rats submitted to open-field and object recognition tests.
In this study age-, circadian rhythm- and methylphenidate administration- effect on open field habituation and object recognition were analyzed. Young and adult male Wistar rats were treated with saline or methylphenidate 2.0 mg/kg for 28 days. Experiments were performed during the light and the dark cycle. Locomotor activity was significantly altered by circadian cycle and methylphenidate treatment during the training session and by drug treatment during the testing session. Exploratory activity was significantly modulated by age during the training session and by age and drug treatment during the testing session. Object recognition memory was altered by cycle at the training session; by age 1.5 h later and by cycle and age 24 h after the training session. These results show that methylphenidate treatment was the major modulator factor on open-field test while cycle and age had an important effect on object recognition experiment.
Gomes
Karin M
KM
Instituto Nacional de Ciência e Tecnologia Translacional em Medicina, Unidade Acadêmica de Ciências da Saúde, Universidade do Extremo Sul Catarinense, Criciúma, SC, Brazil.
Souza
Renan P
RP
Valvassori
Samira S
SS
Réus
Gislaine Z
GZ
Inácio
Cecília G
CG
Martins
Márcio R
MR
Comim
Clarissa M
CM
Quevedo
João
J
D000375:Aging / Q000502:physiology*; D000818:Animals; D000697:Central Nervous System Stimulants / Q000494:pharmacology*; D002940:Circadian Rhythm / Q000502:physiology*; D007858:Learning / Q000187:drug effects; D008297:Male; D008570:Memory, Short-Term / Q000187:drug effects; D008774:Methylphenidate / Q000494:pharmacology*; D009043:Motor Activity / Q000502:physiology; D011597:Psychomotor Performance / Q000187:drug effects*; D051381:Rats; D017208:Rats, Wistar; D021641:Recognition, Psychology / Q000187:drug effects*
D000697:Central Nervous System Stimulants; D008774:Methylphenidate