Fig. 1. Aging alters spontaneous Ca²⁺ event kinetics.

a AAV-GfaABC1D-Lck-GCaMP6f was injected into the DLS of young, middle-aged, and aging mice. Two weeks later, intraventricular injection of tomato lectin (TL) was performed, and striatal brain sections were collected for recording and measuring endfoot Ca²⁺ events in the DLS. b Representative time stacks of young, middle-aged, and aging astrocyte endfeet expressing lck-GCaMP6f (green) immediately adjacent to TL labeled blood vessels (red) in the DLS, scale bar = 15 μm. White arrows point to areas where endfoot Ca²⁺ events initiated. c Example traces of endfoot Ca²⁺ events recorded from young, middle-aged, and aging mice. d Comparisons of the number (left) and area (right) of ROIs generated in young, middle-aged, and aging mice. e ROIs were averaged across individual blood vessels to compare spontaneous Ca²⁺ event frequency (left), amplitude (middle), and duration (right). For young mice: n = 96 ROIs and 36 blood vessels from 7 mice, middle-aged mice: n = 46 ROIs and 16 blood vessels from 4 mice, and for aging mice: n = 57 ROIs and 26 blood vessels from 7 mice. Error bars are S.E.M and all p values are based on Mann-Whitney tests.