Journal
NEUROBIOLOGY OF AGING
Volume 29, Issue 3, Pages 464-470Publisher
ELSEVIER SCIENCE INC
DOI: 10.1016/j.neurobiolaging.2006.10.015
Keywords
mella; MT1; melatonin receptor; circadian; chronobiology; CREB; PACAP; biological rhythms
Categories
Funding
- NIA NIH HHS [P30 AG09975] Funding Source: Medline
Ask authors/readers for more resources
Melatonin modulates circadian rhythms via the hypothalamic suprachiasmatic nucleus (SCN). One of the most robust assays for SCN melatonin receptor activation in mice is the inhibition of PACAP-induced phosphorylation of the transcription factor Ca2+/cAMP responsive element binding protein (CREB). To assess the effect of aging on responsiveness to melatonin, SCN slices from mice of different ages were prepared and treated with PACAP alone or PACAP plus melatonin. CREB phosphorylation state was assessed by immunohistochemistry. In SCN slices from young (2-4-month-old) mice, melatonin reduced the level of phospho-CREB immunoreactivity following PACAP treatment in a dose-dependent manner. In SCN slices from aged mice (19-22 months of age), PACAP alone induced comparable levels of phospho-CREB. but melatonin treatment failed to inhibit the PACAP-induced CREB phosphorylation. The results indicate an age-related loss of sensitivity to melatonin in the SCN. The findings are discussed in the context of the impact of endogenous and exogenous melatonin on sleep in elderly humans. (C) 2006 Elsevier Inc. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available