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Updated: Jul 15, 2026
08:09
Isolation, Culture, and Imaging of Human Fetal Pancreatic Cell Clusters
Published on: May 18, 2014
Insulin receptors in the developing fetal lung
Life Sciences
|December 27, 1982
Summary
Fetal lung insulin receptor numbers increase significantly during rat development. This suggests the developing lung becomes more sensitive to insulin as gestation progresses.
Area of Science:
- Endocrinology
- Developmental Biology
- Pulmonology
Background:
- Insulin plays a crucial role in fetal development.
- Understanding insulin's effects on fetal lung maturation is vital.
Purpose of the Study:
- To investigate changes in fetal lung insulin receptor (InsR) number and affinity during rat gestation.
- To determine if these changes correlate with evolving insulin sensitivity in the developing lung.
Main Methods:
- Quantified insulin receptor binding capacities in rat fetal lungs from 15 to 22 days gestation.
- Assessed high and low affinity receptor constants using radioligand binding assays.
Main Results:
- Insulin receptor binding capacity increased six-fold from 15 to 22 days gestation (approx. 100 to 600 fmoles/mg DNA).
- Receptor affinity constants remained unchanged throughout this developmental period.
Conclusions:
- Fetal lung insulin receptor numbers increase substantially during late gestation.
- The developing lung exhibits enhanced responsiveness to insulin due to increased receptor numbers, not altered affinity.
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