Temporal changes in calcium-binding proteins in the medial geniculate nucleus of the monkey Sapajus apella

• Published in: Journal of chemical neuroanatomy 2015-10, Vol.68, p.45-54
• Main Authors: Campos, Leila M.G., Osório, Elaine C., Santos, Graziela Ligia da Silva, Nogueira, Maria Inês, Cruz-Rizzolo, Roelf J., Pinato, Luciana
• Format: Article
• Language: English
• Subjects: Animals; Auditory Pathways - cytology; Auditory Pathways - metabolism; Auditory system; Biological rhythm; Calbindin 2 - metabolism; Calbindins - metabolism; Calcium-binding proteins; Calcium-Binding Proteins - metabolism; Cebus; Circadian Rhythm; Geniculate Bodies - cytology; Geniculate Bodies - metabolism; Immunohistochemistry; In Vitro Techniques; Male; Neurons - metabolism; Parvalbumins - metabolism; Primate; Thalamus - metabolism
• ISSN: 0891-0618; 1873-6300
• DOI: 10.1016/j.jchemneu.2015.07.005

•The MGN of Sapajus apella exhibits temporal changes in the immunoreactivity of CaBPs;•CB- and CR-IR neurons were predominant during the day and PV-IR at night in the vMGN;•CaBPs-IR neurons showed temporal changes in morphology in the MGN. The subdivisions of the medial geniculate complex can be distinguished based on the immunostaining of calcium-binding proteins and by the properties of the neurons within each subdivision. The possibility of changes in neurochemistry in this and other central auditory areas are important aspects to understand the basis that contributing to functional variations determined by environmental cycles or the animal's cycles of activity and rest. This study investigated, for the first time, day/night differences in the amounts of parvalbumin-, calretinin- and calbindin-containing neurons in the thalamic auditory center of a non-human primate, Sapajus apella. The immunoreactivity of the PV-IR, CB-IR and CR-IR neurons demonstrated different distribution patterns among the subdivisions of the medial geniculate. Moreover, a high number of CB- and CR-IR neurons were found during day, whereas PV-IR was predominant at night. We conclude that in addition to the chemical heterogeneity of the medial geniculate nucleus with respect to the expression of calcium-binding proteins, expression also varied relative to periods of light and darkness, which may be important for a possible functional adaptation of central auditory areas to environmental changes and thus ensure the survival and development of several related functions.