Related Experiment Videos
Effect of light on diurnal variation of blood amino acids in neonates
S Mantagos1, A Moustogianni, A Varvarigou
1Department of Pediatrics, University of Patras Medical School, Greece.
Insights
Newborns
Area of Science:
- Neonatal physiology
- Circadian rhythms
- Biochemistry
Background:
- Normal newborns exhibit diurnal variations in blood amino acid concentrations.
- Amino acid levels are typically lower in the early morning and higher at midday.
- Understanding these variations is crucial for neonatal care.
Purpose of the Study:
- To investigate the impact of different lighting conditions on the diurnal variation of blood amino acids in newborns.
- To determine if continuous light exposure alters normal amino acid patterns.
- To provide insights for optimizing environmental conditions in neonatal units.
Main Methods:
- Three groups of 10 healthy newborns were exposed to distinct lighting conditions for 24 hours.
- Blood amino acid concentrations were measured at 04:00 and 12:00 hours.
- Conditions included continuous light (Group A), eye covering (Group B), and intermittent dimming (Group C).
Main Results:
- Continuous light (Group A) reversed the normal diurnal pattern, decreasing amino acids by 17.7% at midday (p < 0.025).
- Eye covering (Group B) resulted in no significant difference between morning and midday values.
- Intermittent light (Group C) maintained the usual diurnal pattern with a 36.1% increase at midday (p < 0.005).
- Significant differences were observed between continuous light and intermittent light groups (p < 0.0005).
Conclusions:
- Lighting conditions significantly influence the diurnal variation of blood amino acids in newborns.
- Prolonged exposure to continuous light may disrupt normal physiological rhythms.
- Neonatal unit lighting protocols should consider these findings to support infant health.
Abstract:
Normal newborns show a diurnal variation of blood amino acid concentration, with lower values at 04.00 h and higher at 12.00 h. Three groups of infants, each consisting of 10 normal, full-term neonates, remained under different lighting conditions for 24 h and blood amino acids were determined at 04.00 and 12.00 h. Group A remained under continuous light, group B had the eyes covered, and group C was exposed to intermittent light, with the lights dimmed between 22.00 and 04.00 h. Group A showed a reversal of blood amino acid periodicity with a mean decrease of total amino acid concentration by 17.7% at 12.00 h (p less than 0.025). In group B there was no statistically significant difference between 04.00 and 12.00 h values. Group C showed the usual amino acid periodicity with a mean increase of total amino acid concentration by 36.1% at 12.00 h (p less than 0.005). The differences observed between groups A and C were statistically highly significant (p less than 0.0005). These data indicate that lighting conditions may affect the diurnal variation of blood amino acids and this should be considered for infants who remain under continuous light for prolonged periods in neonatal units.