Perfusion of melatonin into the prefrontal cortex disrupts the circadian rhythm of acetylcholine but not of locomotor activity.
Extracellular concentrations of acetylcholine (ACh) in the prefrontal cortex displayed a circadian rhythm, with a maximum increase in the dark phase of the light:dark cycle. The increase in ACh related well to the circadian rhythm of the same rats in which a maximal increase of locomotor activity in the dark phase also was observed. Local perfusion of melatonin (200-500 microm), in a dose-dependent manner, disrupted the ACh rhythm in the prefrontal cortex but did not affect the circadian rhythm of locomotor activity. It is suggested that the change in the cholinergic transmission during a circadian period in the prefrontal cortex may be under the control of the biological clock through the action of melatonin; however, the prefrontal cortical ACh cycle seems not to be related to the regulation of locomotor activity.
de Prado
Blanca Marquez
BM
Department of Physiology, Faculty of Medicine, University Complutense of Madrid, Spain.
Reiter
Russel J
RJ
Mora
Francisco
F
D000109:Acetylcholine / Q000378:metabolism*; D000818:Animals; D002940:Circadian Rhythm / Q000187:drug effects*; D006728:Hormones / Q000494:pharmacology*; D008297:Male; D008550:Melatonin / Q000494:pharmacology*; D009043:Motor Activity; D017397:Prefrontal Cortex / Q000187:drug effects*; D051381:Rats; D013997:Time Factors
D006728:Hormones; D008550:Melatonin; D000109:Acetylcholine