Fig. 3: SMC Ca²⁺ dynamics that underlie myogenic spontaneous vasomotion are prolongedly inhibited by transient ischemia.

a Scheme of timepoints for MCAO surgery, 2PLSM and experimental design. b Representative still-frame images and kymographs of the same MCA before and after ischemic (Occ.2hRep.22 h) stroke. Calcium oscillation in SMCs was reported using SMACreER:Ai96 mice. The turquoise solid line represents the resliced position. c Representative time-lapse calcium oscillation trace of SMC before (dash line) and after (solid line) (Occ.2hRep.22 h) ischemic stroke. Target SMC was labeled in b with turquoise circle. d Basal cytoplasmic Ca²⁺ analyses in SMCs before and after ischemic (Occ.2hRep.22 h) stroke. All data were normalized to the basal value before ischemic stroke (N = 5 mice, n = 40 cells). e Fourier transform analysis of the rhythmic Ca²⁺ oscillation in the arterioles before and after (Occ.2hRep.22 h) ischemic stroke (N = 3 mice). f Statistical analysis of accumulated power (AUC, area under the curve) of Ca²⁺ oscillation within the frequency range of 0–0.3 Hz before and after (Occ.2hRep.22 h) ischemic stroke (N = 3 mice). Calcium index analysis of the Ca²⁺ oscillation in SMCs before and after (Occ.2hRep.22 h) ischemic stroke (N = 5 mice, n = 41 cells), including frequency (g), SD of the peak intervals (h), and amplitude (i). j Scheme of the KCl (300 mM) administration strategy on the brain surface during post-ischemic period and experimental timeline of 2PLSM. k Kymographs of MCA before and after (Occ.2hRep.22 h) ischemic stroke under 2PLSM. Especially, high dose of KCl (300 mM) was administrated at the timepoint of Occ.2hRep.22 h, and a drastic KCl-indused spreading deplorization and vasoconstriction can be observed in these vasomotion/calcium oscillation depressed arterioles (under normal sline treatment conditions). The red signals are the intravenous injected RhoB dye and represents arteriolar lumen. The green signals in the vascular wall represents Ca²⁺ signals indicated by GCaMP6s. l Time-lapse fluorescent GcaMP6s signal changes trace in the MCA along with ischemic stroke, and high dose of KCl administration (N = 3 mice). Data are expressed as the mean ± SEM. All data were analyzed using unpaired t tests.