title: Periodic analysis of ultradian (40 min less than tau less than 24h) respiratory variations in laboratory vertebrates of various circadian activities.
abstract: Continuous recordings of respiratory gas exchanges of various laboratory endotherm vertebrate species, which have either a nocturnal (mouse, rat) or diurnal (monkey, quail, chicken) or equivocal (guinea-pig) maximal activity, kept under controlled environmental conditions of temperature, humidity, ventilation and provided with food and water ad libitum, show ultradian oscillations of mean and low frequencies (1 less than f less than 35 c.day-1). Harmonic analysis was used to assess periodic or random ultradian variations and to compute amplitudes and phases of these oscillations when these vertebrates were submitted to a light (100 lx) and dark circadian alteration (LD 12:12). Spectral analysis shows that a 100-lx continuous illumination or continuous darkness decreases circadian respiratory rhythms and increases these ultradian respiratory oscillations.
mesh_terms: D000818:Animals; D002245:Carbon Dioxide / Q000502:physiology; D002645:Chickens; D002940:Circadian Rhythm; D003624:Darkness; D006168:Guinea Pigs; D008027:Light; D008252:Macaca fascicularis; D008297:Male; D051379:Mice; D010100:Oxygen / Q000502:physiology; D051381:Rats; D012119:Respiration; D013045:Species Specificity; D013057:Spectrum Analysis
chemical_list: D002245:Carbon Dioxide; D010100:Oxygen