Wake-promoting agent modafinil worsened attentional performance following REM sleep deprivation in a young-adult rat model of 5-choice serial reaction time task.
BACKGROUND
Individuals who experience sleep loss may exhibit certain physiological abnormalities. Central stimulant drugs have been studied in sleep-loss conditions, and some of them might be therapeutically beneficial. Modafinil (diphenyl-methyl-sulfinyl-2-acetamide, MOD) has been increasingly employed for elevating alertness and vigilance in recent years, yet the underlying mechanism of actions for MOD is not fully understood.


OBJECTIVE
To examine the behavioral effect of MOD following rapid eye movement sleep deprivation (REMD) in rats. A five-choice serial reaction time task (5-CSRTT) was employed to investigate animals' attentional performance and impulsive reactivity.


METHODS
Rats of different ages were trained to learn the 5-CSRTT. REMD with the water platform method was applied for 96 h. The impacts of REMD on 5-CSRTT in middle-age (32-weeks-old) and young-adult (12-week-old) rats were compared with baseline or a condition with shorter visual stimulus duration.


RESULTS
The results revealed that following REMD, young-adult but not middle-age rats were liable to be affected in their performances of the 5-CSRTT. In young-adult rats, while MOD had no contributions to the effect of REMD, it worsened rats' performance following REMD when the stimulus duration was shortened, as shown by the reduced number of correct responses and prolonged magazine latency.


CONCLUSIONS
These results suggest that aging might be a crucial factor for the physiological impact following REMD. MOD should be used cautiously, particularly, in conditions that require REM sleep.
Liu
Yia-Ping
YP
Department of Physiology and Biophysics, National Defense Medical Center, Min-Chuan East Road, Taipei 114, Taiwan, Republic of China. yiaping@ms75.hinet.net
Tung
Che-Se
CS
Lin
Yu-Lung
YL
Chuang
Chia-Hsin
CH
D000367:Age Factors; D000818:Animals; D001288:Attention / Q000187:drug effects*; D001559:Benzhydryl Compounds / Q000494:pharmacology*; D000697:Central Nervous System Stimulants / Q000494:pharmacology*; D002755:Choice Behavior / Q000187:drug effects*; D008297:Male; D000077408:Modafinil; D009043:Motor Activity / Q000187:drug effects; D010775:Photic Stimulation / Q000379:methods; D051381:Rats; D017207:Rats, Sprague-Dawley; D011930:Reaction Time / Q000187:drug effects*; D012892:Sleep Deprivation / Q000523:psychology*; D013997:Time Factors
D001559:Benzhydryl Compounds; D000697:Central Nervous System Stimulants; D000077408:Modafinil