Ultradian and circadian compartmentalization of respiratory and metabolic exchanges in small laboratory vertebrates.
Carbon dioxide emission (VCO2) taken as an index of respiratory and metabolic exchanges, was continuously recorded during 4-30 consecutive days in 100 quail, 87 chicks, 347 rats, 665 mice and 70 guinea-pigs which were under controlled environmental parameters. Harmonic analysis, fast Fourier transform, chi-square periodograms, peak and trough intervals were computed with VCO2 values obtained with CO2 concentrations sampled every 20 min on the CO2 recordings. In LD 12:12 alternation, circadian rhythms were observed in all quail, chicks, rats and mice, but only in 80% of the guinea-pigs. Ultradian VCO2 rhythms, with periods which show statistically significant interspecies differences, were assessed. For each of the 5 species these computed periods, which were the same in LL and DD, were: 1.17 h for quail and chickens, 1.25 h for rats, 1.50 h for mice and 1.0 h for guinea-pigs. In LD 12:12 these periods were different during L and D in quail, chicks, rats and mice, but not in guinea-pigs. The amplitudes of these ultradian variations were, according to the species, 10-20% of their mean VCO2 levels. These ultradian rhythms persist in the absence (or masking) of circadian rhythms, e.g. in LD 12:12 in 20% of guinea-pigs and in LL in 87% of Japanese quail and in 23% of Sprague-Dawley rats. Moreover, these ultradian rhythms persist during starvation, locomotor activity restraint and ageing. These ultradian VCO2 cycles which are related to rest-activity variations appear to be basic physiological rhythms with a genetic origin.
Stupfel
M
M
French National Institute of Health and Medical Research (INSERM), Le Vésinet.
Gourlet
V
V
Perramon
A
A
Mérat
P
P
Court
L
L
D000204:Activity Cycles / Q000502:physiology*; D000818:Animals; D002245:Carbon Dioxide; D002645:Chickens; D002940:Circadian Rhythm / Q000502:physiology*; D003370:Coturnix; D005260:Female; D008297:Male; D008660:Metabolism; D051379:Mice; D010101:Oxygen Consumption; D051381:Rats; D012119:Respiration / Q000502:physiology*; D013045:Species Specificity
D002245:Carbon Dioxide