Table 3.

Estimates of rhythm parameters for core clock genes in ventral C3–C5 spinal cord, caudal medulla, and diaphragm muscle homogenates calculated using cosinor analysis

Gene/Region	Mesor	Amplitude (95% CI)	Acrophase (ZT; h:min)	Cosinor P Value	ANOVA P Value
Bmal1
Ventral C3–C5 spinal cord	0.86	0.25 (0.17, 0.32)	1:14	P = 5.57E−9*	P = 2.38E−8*
Medulla	0.83	0.27 (0.20, 0.35)	1:34	P = 3.61E−10*	P = 3.20E−8*
Diaphragm	0.53	0.56 (0.43, 0.70)	2:19	P = 1.73E−11*	P = 3.42E−12*
Clock
Ventral C3–C5 spinal cord	0.93	0.09 (0.02, 0.15)	1:41	P = 0.004*	P = 0.013*
Medulla	0.90	0.09 (0.02, 0.16)	2:23	P = 0.004*	P = 0.006*
Diaphragm	0.76	0.26 (0.14, 0.37)	3:08	P = 5.51E−6*	P = 1.38E−5*
Per1
Ventral C3–C5 spinal cord	1.14	0.40 (0.27, 0.53)	13:21	P = 1.87E−8*	P = 4.04E−8*
Medulla	1.11	0.36 (0.18, 0.53)	12:13	P = 3.06E−5*	P = 1.19E−4*
Diaphragm	1.59	1.26 (0.90, 1.63)	12:04	P = 1.59E−9*	P = 1.20E−7*
Per2
Ventral C3–C5 spinal cord	1.38	0.60 (0.38, 0.81)	15:14	P = 1.08E−7*	P = 1.12E−7*
Medulla	1.35	0.53 (0.37, 0.68)	14:10	P = 1.19E−9*	P = 2.44E−9*
Diaphragm	4.76	4.55 (2.41, 6.69)	15:46	P = 1.64E−5*	P = 4.18E−11*

Numerical values for mesor, amplitude, acrophase, and significance of the rhythm (cosinor P value; H₀: amplitude = 0) are presented. Additionally, a one-way ANOVA was conducted to determine an overall effect of time (ANOVA P value; H₀: all time point means are equal). Mesor is the midline estimating statistic of rhythm in fold change relative to ZT5. Amplitude is half the value of the range of oscillation in fold change. Acrophase is the predicted time of peak mRNA expression (h:min). Time in hours is denoted by ZT because light is a zeitgeber. ZT0 = lights on (rest onset) in the entrained cycle, and ZT12 = lights off (active onset); CI, confidence interval.

^*Significance of daily rhythmicity (P < 0.05).