Related Experiment Videos
Sequential intravenous glucose tolerance: responses of newborn and adult
Insights
Infant glucose metabolism differs from adults, showing higher insulin responses and variability. Despite similar starting insulin, infant glucose disposal rates were slower, with significant individual differences observed.
Area of Science:
- Endocrinology
- Metabolic Research
- Pediatric Physiology
Background:
- Understanding glucose-insulin dynamics is crucial for metabolic health.
- Infant metabolic responses may differ significantly from adults.
- Gestational diabetes can impact fetal development and infant metabolism.
Purpose of the Study:
- To compare glucose disposal and insulin response in adults and infants.
- To investigate metabolic differences in infants of mothers with gestational diabetes.
- To analyze the variability of glucose tolerance tests in infants.
Main Methods:
- Acute sequential intravenous glucose tolerance tests (IVGTT) were administered.
- Tests were conducted at 120-minute intervals in fasting participants.
- Participants included normal adults, normal infants, and infants of diabetic mothers.
Main Results:
- Adult glucose disposal (Kt) and insulin elevations were consistent in paired studies.
- Infant studies exhibited high variability despite similar initial insulin levels (<10 micronU/ml).
- Infants showed slightly slower glucose disposal rates (1.43-1.47%/min) than adults (1.66%/min) but higher, more sustained insulin responses.
Conclusions:
- Infant glucose-insulin dynamics are characterized by greater variability and distinct patterns compared to adults.
- Heterogeneity in infant responses complicates direct comparisons between infant groups.
- Further research is needed to elucidate the specific factors contributing to infant metabolic variability.
Abstract:
Acute sequential intravenous glucose tolerance tests were performed at an interval of 120 min in 12 normal fasting adults, 5 normal infants, and 6 infants of gestationally diabetic mothers. Glucose disposal (Kt) and plasma insulin elevations were remarkably similar in the paired adult studies. In contrast, the studies in all infants were highly variable although they had similar initial plasma insulin levels (less than 10 micronU/ml). The rates of glucose disposal in the infants (1.43 and 1.47%/min) were slightly slower than the adult rates (1.66%/min). The plasma insulin responses, in contrast, were higher and more sustained throughout the second half of the test in the infants as a group. There was remarkable heterogeneity in the responses of the infants which obscured any differences between the groups.