Fig. 2: VIP-Ca2+ changes to a weak, long-period rhythm at the late stage in DD in VIP-deficient mice.
From: Neuronal feedback loop of the suprachiasmatic nucleus generates robust circadian rhythms
a Averaged periodograms of detrended AVP-Ca2+ (green), VIP-Ca2+ (magenta) signals, and the locomotor activity (black) of control and VIP-deficient mice for days 1–20 in DD (10-min bins). Black dotted line, 24 h. b, c Mean period and amplitude (Qp values) of Ca2+ rhythms in DD. Here, peak periods are first calculated from individual mice’s periodograms and then averaged. Time courses of periods (d) and amplitudes (Qp) (e) of AVP- Ca2+ (green), VIP-Ca2+ (magenta), and the locomotor activity (black) rhythms in DD by sequential periodogram analyses with 5-day shifting windows. Values are mean ± SEM. n = 5 for control; n = 8 for VIP-deficient mice. *p < 0.05, **p < 0.01, ***p < 0.001 by two-tailed Student’s or Welch’s t test (b, c), one-way (b, c) or two-way repeated measures (d) ANOVA; ns not significant. The exact p-values are as follows: AVP-Ca2+, <0.0001; VIP-Ca2+, Control vs. VIP-deficient (Primary), <0.0001, Control vs. VIP-deficient (Secondary), 0.0037, VIP-deficient (Primary) vs. VIP-deficient (Secondary), <0.0001 (b), AVP-Ca2+, 0.0009; VIP-Ca2+, Control vs. VIP-deficient (Primary), <0.0001, Control vs. VIP-deficient (Secondary), <0.0001, VIP-deficient (Primary) vs. VIP-deficient (Secondary), 0.1153 (c), Control, 0.9178; VIP-deficient, AVP-Ca2+ vs. VIP-Ca2+, 0.0033, AVP-Ca2+ vs. Locomotor activity, 0.0006, VIP-Ca2+ vs. Locomotor activity, >0.9999 (d). Gray lines indicate the 99.9% confidence levels in χ2 periodograms (a, e). Source data are provided as a Source Data file.
