Abstract 327 Poster Session IV, Tuesday, 5/4 (poster 246)
Neonatal development of circadian rhythm (CR) is a fundamental expression of brain maturation. We have developed a non-human primate model to study CR in early infancy. Eleven infants of pregnant baboons (gestational age 167-193 days) were delivered by caesarian section. To eliminate the influence of maternal factors and test endogenous CR in the absence of any time cues we hand reared all infants from birth under continuous low light. Newborns were implanted with a telethermometer to record body temperature every 4 s. CR amplitude was measured based on peak and trough differences of body temperature in each 24 h cycle. A significant endogenous CR was present from the 1st week of life. CR amplitude increased as a function of age in all infants (figure). These data are consistent with the hypothesis that CR develops independent of external factors in primates and is a measure of brain maturity.
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This study was founded by NIH Grant HD28014
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(Spon by: Ronald L Ariagno)
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Mirmiran, M., Bernardo, L., Xiao H et al. Development of Circadian Rhythms in Newborn Baboons. Pediatr Res 45, 57 (1999). https://doi.org/10.1203/00006450-199904020-00344
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DOI: https://doi.org/10.1203/00006450-199904020-00344
