Modulation of intercellular calcium signaling by melatonin in avian and mammalian astrocytes is brain region-specific.

TitleModulation of intercellular calcium signaling by melatonin in avian and mammalian astrocytes is brain region-specific.
Publication TypeJournal Article
Year of Publication2005
JournalThe Journal of comparative neurology
Volume493
Issue3
Pagination370-80
Date Published2005
ISSN0021-9967
Abstract

Calcium waves among glial cells impact many central nervous system functions, including neural integration and brain metabolism. Here, we characterized the modulatory effects of melatonin, a pineal neurohormone that mediates circadian and seasonal processes, on glial calcium waves derived from different brain regions and species. Diencephalic and telencephalic astrocytes, from both chick and mouse brains, expressed melatonin receptor proteins. Further, using the calcium-sensitive dye Fluo-4, we conducted real-time imaging analyses of calcium waves propagated among mammalian and avian astrocytes. Mouse diencephalic astrocytic calcium waves spread to an area 2-5-fold larger than waves among avian astrocytes and application of 10 nM melatonin caused a 32% increase in the spread of these mammalian calcium waves, similar to the 23% increase observed in chick diencephalic astrocytes. In contrast, melatonin had no effect on calcium waves in either avian or mammalian telencephalic astrocytes. Mouse telencephalic calcium waves radially spread from their initiation site among untreated astrocytes. However, waves meandered among mouse diencephalic astrocytes, taking heterogeneous paths at variable rates of propagation. Brain regional differences in wave propagation were abolished by melatonin, as diencephalic astrocytes acquired more telencephalon-like wave characteristics. Astrocytes cultured from different brain regions, therefore, possess fundamentally disparate mechanisms of calcium wave propagation and responses to melatonin. These results suggest multiple roles for melatonin receptors in the regulation of astroglial function, impacting specific brain regions differentially.

URLhttp://dx.doi.org/10.1002/cne.20779
DOI10.1002/cne.20779
Short TitleJ Comp Neurol
X
Enter your linkblue username.
Enter your linkblue password.
Secure Login

This login is SSL protected

Loading