Ontogenic changes and regulation of renal angiotensin II type 1 receptor gene expression during fetal and newborn life. Pediatr Res 1994 Dec;36(6):755-62
Date
12/01/1994Pubmed ID
7898984DOI
10.1203/00006450-199412000-00013Scopus ID
2-s2.0-0028127366 (requires institutional sign-in at Scopus site) 45 CitationsAbstract
Factors regulating the expression of the angiotensin II subtype 1 (AT1) receptor during fetal life have not been investigated previously. The present study was designed 1) to characterize the ontogeny of AT1 receptor gene expression in the kidney of fetal and newborn sheep and 2) to determine the influence of both glucocorticoids and renal nerves in modulating AT1 gene expression during fetal life and during the transition from fetal to newborn life. We first isolated and cloned a PCR product that has 98 and 94% homology with the cDNA encoding the bovine and pig AT1 receptors, respectively, and 99 and 98% homology with the corresponding deduced protein sequences. Probing with this cDNA, we demonstrated that renal AT1 mRNA expression did not change significantly during the last trimester of gestation in fetal sheep or immediately after birth but decreased significantly 10 d after birth. We also demonstrated that renal denervation in the fetus had no effect on renal AT1 gene expression in 24-h-old newborn lambs. On the other hand, we observed in 130-d twin fetuses that a continuous intraperitoneal infusion (1 mL/h) of cortisol (3 mg/h or 6.2 mumol/h) for 48 h in one of the twins increased the fetal plasma cortisol concentration from 32.0 +/- 7.1 to 1126 +/- 231 nmol/L and produced a significant decrease (p < 0.005) in renal AT1 gene expression compared with the control twin receiving an intraperitoneal infusion of 0.9% NaCl. In summary, this study demonstrates that renal AT1 gene expression is elevated during fetal life and decreases after birth. It is also shown that glucocorticoids, but not renal nerves, contribute to the regulation of renal AT1 gene expression during development.
Author List
Robillard JE, Schutte BC, Page WV, Fedderson JA, Porter CC, Segar JLAuthor
Jeffrey L. Segar MD Professor in the Pediatrics department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
Amino Acid SequenceAnimals
Base Sequence
Embryonic and Fetal Development
Gene Expression Regulation, Developmental
Humans
Hydrocortisone
Infant, Newborn
Kidney
Molecular Sequence Data
Receptors, Angiotensin
Sheep