Table 1

Peak phases of bioluminescence (mean ± SEM, in hours after last lights-on) in the SCN, skeletal muscle, liver, and lung. The effect of advancing or delaying the light schedule by 6 or 9 hours was measured on the first or sixth cycles following the shift in the light cycle. Average phase shifts (in parentheses) were measured relative to the average peak phase of tissues taken from control animals. The magnitude of the phase shifts of the different tissues were compared to that observed in the SCN.

TreatmentSCNSkeletal muscleLiverLung
Control30.9  ±  0.741.3  ±  1.242.1  ±  1.438.1  ±  1.3
6 hour delay 1st35.8  ±  0.8* (−4.9)45.2  ±  0.9* (−3.9)41.0  ±  1.1 (+1.1) 41.7  ±  0.7* (−3.6)
6 hour delay 6th36.9  ±  0.8* (−6.0)47.9  ±  0.2* (−6.6)45.6  ±  0.0 (−3.5) 44.2  ±  0.7* (−6.1)
6 hour advance 1st25.9  ±  0.5* (+5.0)AR 40.1  ±  0.6 (+2.0) 39.2  ±  0.2 (−1.1)
6 hour advance 6th24.9  ±  0.8* (+6.0)35.9  ±  1.0* (+5.4)35.8  ±  0.4* (+6.3)32.6  ±  0.4* (+5.5)
9 hour delay 1st40.2  ±  0.7* (−9.3)44.6  ±  1.3 (−3.3)Not testedNot tested
9 hour advance 1st23.1  ±  0.2* (+7.8)AR§ Not testedNot tested
  • * Significant phase shift; ANOVA followed by Dunnetts test,P < 0.05.

  • Significantly smaller shift than in the SCN, ANOVA followed by Dunnetts test, P < 0.05.

  • Two muscle cultures were rhythmic with peak at 34.8 (+6.5), four muscle cultures had low-amplitude rhythms with peak around 37.2 (+4.1), two muscle cultures were arrhythmic.

  • § All muscle cultures were arrhythmic.