title: Intrinsic organization of the suprachiasmatic nucleus in the capuchin monkey.
abstract: The suprachiasmatic nucleus (SCN), which is the main circadian biological clock in mammals, is composed of multiple cells that function individually as independent oscillators to express the self-sustained mRNA and protein rhythms of the so-called clock genes. Knowledge regarding the presence and localization of the proteins and neuroactive substances of the SCN are essential for understanding this nucleus and for its successful manipulation. Although there have been advances in the investigation of the intrinsic organization of the SCN in rodents, little information is available in diurnal species, especially in primates. This study, which explores the pattern of expression and localization of PER2 protein in the SCN of capuchin monkey, evaluates aspects of the circadian system that are common to both primates and rodents. Here, we showed that PER2 protein immunoreactivity is higher during the light phase. Additionally, the complex organization of cells that express vasopressin, vasoactive intestinal polypeptide, neuron-specific nuclear protein, calbindin and calretinin in the SCN, as demonstrated by their immunoreactivity, reveals an intricate network that may be related to the similarities and differences reported between rodents and primates in the literature.
authors.affiliation: Department of Anatomy, Institute of Biomedical Sciences, University of São Paulo, SP, Brazil.
authors.forename: V A
authors.initials: VA
authors.lastname: Rocha
authors.affiliation: Department of Anatomy, Institute of Biomedical Sciences, University of São Paulo, SP, Brazil.
authors.forename: R
authors.initials: R
authors.lastname: Frazão
authors.affiliation: Department of Anatomy, Institute of Biomedical Sciences, University of São Paulo, SP, Brazil.
authors.forename: L M G
authors.initials: LM
authors.lastname: Campos
authors.affiliation: Department of Anatomy, Institute of Biomedical Sciences, University of São Paulo, SP, Brazil.
authors.forename: P
authors.initials: P
authors.lastname: Mello
authors.affiliation: Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, SP, Brazil.
authors.forename: J
authors.initials: J
authors.lastname: Donato
authors.affiliation: Department of Basic Sciences, São Paulo State University Araçatuba, SP, Brazil.
authors.forename: R J
authors.initials: RJ
authors.lastname: Cruz-Rizzolo
authors.affiliation: Department of Anatomy, Institute of Biomedical Sciences, University of São Paulo, SP, Brazil.
authors.forename: M I
authors.initials: MI
authors.lastname: Nogueira
authors.affiliation: Department of Speech Language and Hearing Therapy, São Paulo State University, Marília, SP, Brazil. Electronic address: lpinato@marilia.unesp.br.
authors.forename: L
authors.initials: L
authors.lastname: Pinato
mesh_terms: D000818:Animals; D001127:Arginine Vasopressin / Q000378:metabolism; D064032:Calbindin 2 / Q000378:metabolism; D064026:Calbindins / Q000378:metabolism; D002428:Cebus; D002940:Circadian Rhythm / Q000235:genetics; D015870:Gene Expression / Q000502:physiology*; D008297:Male; D009419:Nerve Tissue Proteins / Q000378:metabolism; D056950:Period Circadian Proteins / Q000235:genetics / Q000378:metabolism*; D010775:Photic Stimulation; D012333:RNA, Messenger / Q000378:metabolism; D012701:Serotonin / Q000378:metabolism; D013493:Suprachiasmatic Nucleus / Q000378:metabolism*; D014660:Vasoactive Intestinal Peptide / Q000378:metabolism
chemical_list: D064032:Calbindin 2; D064026:Calbindins; D009419:Nerve Tissue Proteins; D056950:Period Circadian Proteins; D012333:RNA, Messenger; D001127:Arginine Vasopressin; D012701:Serotonin; D014660:Vasoactive Intestinal Peptide
keywords: Biological rhythms; Diurnal monkey; Neuroanatomy; Per2