Grant: Travel Awards - Institute Community Support

Astrocytes (star-shaped glial cells) are increasingly recognized to be involved in neurodegenerative disorders such as Alzheimer's Disease and Parkinson's Disease. In addition, chronic stress and loss of mediators such as serotonin (5HT), norepinephrine, and acetylcholine is also characteristic of these disorders. It is known that corticosterone (CORT; the main stress hormone in rodents) and 5HT have actions on astrocytes and that they affect inhibitory networks in the cortex. Therefore, we assessed the role of CORT and 5HT on astrocytes using a paired-pulse stimulation protocol in C57Bl6 mouse brain slices. Stimulation produces evoked potentials, and suppression of the second pulse normally occurs due to presence of inhibitory interneurons firing. We found CORT and 5HT affect inhibition and differentially use purinergic (ATP and adenosine) signaling to do so. Using iodoacetate, a glycolysis blocker that is believed to selectively inhibit astrocytes, we identified a potential role of astrocytes in the CORT and 5HT effects on inhibition. These results provide insight in to the importance of astrocytes in stress and neuromodulator function, possibly indicating a route through which astrocytes are affected in age-related disorders.