Bacterial lipopolysaccharide (LPS)-induced type 2 iodothyronine deiodinase (D2) activation in the mediobasal hypothalamus (MBH) is independent of the LPS-induced fall in serum thyroid hormone levels.
By administration of bacterial lipopolysaccharide (LPS) to intact and T4-replaced thyroidectomized rats, we demonstrate that in contrast to the cortex and anterior pituitary, there is a persistent increase in type 2 iodothyronine deiodinase (D2) activity in the mediobasal hypothalamus (MBH). We propose that endotoxin-induced D2 activation in the MBH is independent of circulating levels of thyroid hormone and that this mechanism may contribute to central hypothyroidism associated with infection.
Fekete
Csaba
C
Tupper Research Institute and Department of Medicine, Division of Endocrinology, Diabetes, and Metabolism, Tufts-New England Medical Center, 750 Washington St., Boston, MA 02111, USA.
Sarkar
Sumit
S
Christoffolete
Marcelo A
MA
Emerson
Charles H
CH
Bianco
Antonio C
AC
Lechan
Ronald M
RM
D000818:Animals; D001831:Body Temperature / Q000187:drug effects; D004789:Enzyme Activation / Q000187:drug effects; D007033:Hypothalamus, Middle / Q000187:drug effects*; D007453:Iodide Peroxidase / Q000378:metabolism*; D008070:Lipopolysaccharides / Q000494:pharmacology*; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D013963:Thyroid Hormones / Q000097:blood*; D013965:Thyroidectomy / Q000379:methods; D013997:Time Factors; D000097564:Iodothyronine Deiodinase Type II
D007453:Iodide Peroxidase; D008070:Lipopolysaccharides; D013963:Thyroid Hormones; D000097564:Iodothyronine Deiodinase Type II