Thyroid Hormone Regulates Renocortical COX-2 and PGE2 Expression in the Late Gestation Fetal Sheep

Department of Obstetrics and Gynecology, Wake Forest University School of Medicine, Winston-Salem, North Carolina 27157, USA.
Reproductive sciences (Thousand Oaks, Calif.) (Impact Factor: 2.23). 08/2008; 15(6):598-603. DOI: 10.1177/1933719108316910
Source: PubMed


Cyclooxygenase 2 (COX-2) is important for development of the fetal kidney. Precisely how renal COX-2 expression is regulated in fetal life is unclear. The hypothesis that thyroid hormone positively regulates COX-2 and PGE(2) levels in the late gestation fetal kidney cortex was tested. Sham, thyroidectomized (TX), and TX + thyroid hormone replacement (R) fetal sheep were studied. TX was performed at 120 days gestational age (dGA). TX + R fetuses were continuously infused with thyroxine from 3 days after surgery until study completion. Fetal kidney cortex was obtained at 137 dGA for measurement of renal cyclooxygenase type-2 (COX-2) protein and PGE(2) metabolites. Renocortical COX-2 and PGE(2) levels were significantly lower in TX compared with sham and TX + R fetuses. There were no differences between sham and TX + R fetuses. These findings demonstrate that thyroid hormone positively regulates renal COX-2 and PGE(2) expression in the late gestation fetal sheep kidney.

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