[Relationship between serum thyroid hormone and GH-IGF axis, growth failure in nephrotic rats].
OBJECTIVE
To investigate the individual effects of malnutrition, nephrosis and glucocorticoid therapy on serum thyroid hormone, and explore the relationship between serum thyroid hormone and GH-IGF axis, growth failure in nephrotic rats.


METHODS
Twenty-four male Sprague-Dawley (SD) rats were randomly divided into control group, pair-fed group, doxorubincin-induced nephrotic group (nephrotic group) and dexamethasone-treated nephrotic group (des-treated group). Serum T3/T4, GH and IGF-I were measured by RIA, serum IGFBPs were measured by Western ligand blot, liver GHR and IGF-I/IGFBPs mRNA were analyzed by radio-receptor assay and RT-PCR respectively.


RESULTS
1. Serum thyroid hormone was low in pair-fed group, lower in nephrotic group and lowest in des-treated group except for high serum T4 in pair-fed group. 2. Serum thyroid hormone was positively related with liver GHR, IGF-I/IGFBP-3 mRNA and serum IGF-I/IGFBP-3, and negatively related with serum IGFBP-2. 3. Serum thyroid hormone was positively related with nose-tail length and weight (both P < 0.01).


CONCLUSIONS
The hypothyroidism is a possible mechanism of reducing serum IGF-I levels and biologic action, and resulting in growth failure in nephrotic syndrome.
Liu
J H
JH
Department of Pediatrics, Second Xiangya Hospital, Central South University, Changsha 410011, China.
Yi
Z W
ZW
D000818:Animals; D004317:Doxorubicin; D006130:Growth Disorders / Q000209:etiology*; D008297:Male; D009404:Nephrotic Syndrome / Q000097:blood* / Q000139:chemically induced / Q000503:physiopathology; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley; D013002:Somatomedins / Q000378:metabolism*; D013974:Thyroxine / Q000097:blood*; D014284:Triiodothyronine / Q000097:blood
D013002:Somatomedins; D014284:Triiodothyronine; D004317:Doxorubicin; D013974:Thyroxine