Neuroscience Research · Mar 10, 2017

Retinal, NPY- and 5ht- inputs to the aged suprachiasmatic nucleus in common marmosets (Callithrix jacchus)

By Engelberth RCGJ, Silva KDA, Fiuza FP et al.

The circadian timing system (CTS) anticipates optimal physiological patterns in response to environmental fluctuations, such as light-dark cycle. Since age-related disruption of circadian synchronization is linked to several pathological conditions, we characterized alterations of neurochemical constituents and retinal projections to the major pacemaker of CTS, the suprachiasmatic nucleus (SCN), in adult and aged marmosets. We used intraocular injections of neural tracer Cholera toxin b (CTb) to report age-related reductions in CTb, neuropeptide Y and serotonin immunoreactivities. Considering these projections arise in SCN from nuclei that relay environmental information to entrain the circadian clock, we provide important anatomical correlates to age-associated physiological deficits.

doi.org/10.1016/j.neures.2017.03.005PubMed 28288865Mechanisms