Table 1.

Mean (± SE) values of non-REM and REM sleep time, cortical brain temperature, feeding activity, plasma leptin and ghrelin concentrations, and hypothalamic ghrelin contents in 24-h, in the 12-h light period, and in the 12-h dark period in rats free-feeding on normal diurnal rhythm and in rats with food restricted to the 12-h light period

Free FeedingRestricted Feeding
NREMS, %Rec time
    Total43.5±0.4243.0±0.44
    Light61.4±0.5450.3±0.62*
    Dark25.7±0.7835.6±0.63*
REMS, %Rec time
    Total8.4±0.198.9±0.15
    Light12.4±0.376.2±0.25*
    Dark4.5±0.2711.5±0.31*
Tcrt, °C
    24 h37.6±0.0837.7±0.08
    Light37.2±0.0937.6±0.09*
    Dark38.1±0.0837.7±0.09*
Feeding Activity, %24 h
    Light13.5±1.67100
    Dark86.5±1.620
Leptin, ng/ml
    24 h3.5±0.245.3±0.47*
    Light2.6±0.156.6±0.71*
    Dark4.6±0.383.7±0.33
    Peak6.2±0.917.8±0.72
Plasma ghrelin, pg/ml
    24 h1,333.3±77.581,735.4±142.23*
    Light1,549.0±123.541,247.7±91.96*
    Dark1,099.6±64.602,365.3±252.96*
    Peak1,857.7±257.533,649.8±401.12*
Hypothalamic ghrelin, pg/mg
    24 h1.04±0.0271.10±0.018*
    Light1.01±0.0381.07±0.020
    Dark1.07±0.0381.15±0.029
  • Values are means ± SE. REM, rapid eye movement; REMS, REM sleep; NREMS, non-REM sleep; Tcrt, cortical brain temperature; %Rec time, % recording time.

  • * Significant difference (Student t-test) between free-feeding rats and rats on restricted feeding.