MelatoninReceptors, MelatoninReceptor, Melatonin, MT1Receptor, Melatonin, MT2Pineal GlandBrain ChemistryBrain InjuriesBrain NeoplasmsCircadian RhythmArylalkylamine N-AcetyltransferaseBrain MappingTryptaminesAcetylserotonin O-MethyltransferaseBrainBrain EdemaPhotoperiodBrain StemBrain IschemiaMagnetic Resonance ImagingLightBrain AbscessKynuramineAntioxidantsRats, Sprague-DawleyRats, WistarNeuronsSleepCerebral CortexHypoxia, BrainBlood-Brain BarrierSleep Disorders, Circadian RhythmTime FactorsDrug ImplantsBrain Damage, Chronic5-MethoxytryptamineSeasonsBrain InfarctionChronobiology DisordersDose-Response Relationship, DrugDisease Models, AnimalPeriodicityBody TemperatureDarknessSerotoninNeuroprotective AgentsProlactinDeep Brain StimulationHippocampusSheepNerve Tissue ProteinsSuprachiasmatic NucleusCentral Nervous System DepressantsTissue DistributionRNA, Messenger