Related Experiment Videos
Corticosteroid-binding globulin biosynthesis in the mouse liver and kidney during postnatal development
L A Scrocchi1, S A Hearn, V K Han
1Medical Research Council Group in Fetal and Neonatal Health and Development, University of Western Ontario, London, Canada.
Endocrinology
|February 1, 1993
Summary
Kidney tubules, not just the liver, produce corticosteroid-binding globulin (CBG) during early development. This local CBG production in the kidney may influence glucocorticoid activity and renal maturation.
Area of Science:
- Endocrinology
- Developmental Biology
- Renal Physiology
Background:
- Plasma corticosteroid-binding globulin (CBG) is primarily synthesized by the liver.
- CBG influences glucocorticoid bioavailability.
- Glucocorticoids are crucial for postnatal renal development.
Purpose of the Study:
- To investigate the sites of CBG biosynthesis during postnatal development.
- To determine the role of kidney-produced CBG in local glucocorticoid bioavailability.
- To understand the developmental expression of CBG in the liver and kidney.
Main Methods:
- In situ hybridization to detect CBG mRNA.
- Immunohistochemistry to localize CBG protein.
- Western blot analysis to assess CBG degradation in urine.
Main Results:
- Neonatal mouse kidneys, specifically developing tubules, are active sites of CBG biosynthesis.
- CBG and its mRNA colocalize to proximal convoluted tubules of juxtamedullary nephrons by 7 days.
- Liver CBG production increases post-10 days, while kidney CBG mRNA peaks by week 3 and declines.
- CBG is secreted into the tubular lumen and proteolytically degraded in urine.
Conclusions:
- The developing kidney is a significant site of CBG biosynthesis, in addition to the liver.
- Kidney-derived CBG may modulate local glucocorticoid action, influencing renal tubule maturation.
- Proteolytic degradation of CBG in urine is associated with increased kidney biosynthesis.