Document Detail

Thyroid hormones regulate the onset of osmotic activity of rat liver mitochondria after birth.
MedLine Citation:
PMID:  9003013     Owner:  NLM     Status:  MEDLINE    
The effect of thyroid hormone deprivation on the osmotic activity of liver mitochondria from early newborn rats was studied. Experimentally induced hypothyroidism prevented the increase in the osmotic activity of mitochondria observed immediately after birth. Osmotic activity was restored by T4 and T3 treatment to hypothyroid newborns but not when this treatment was supplemented with cycloheximide. Under the same circumstances, streptomycin had no effect. Hypothyroidism abolished the change in the slope of the osmotic curve (plot of inverse absorbance of mitochondrial suspensions incubated in sucrose solutions vs. inverse sucrose concentration) observed in mitochondria from euthyroid newborns at 110-120 mOsm sucrose, suggesting that hypothyroidism prevents the formation of tight physical connections between mitochondrial outer and inner membranes. Thyroid hormone deprivation increased the passive permeability of the mitochondrial inner membrane to protons, resulting in a decreased respiratory control ratio. Hypothyroidism prevented the sharp decrease in the affinity of mitochondria for ATP observed in euthyroid newborns immediately after birth. These results corroborate our previous suggestion (Endocrinology, 1995, 136:4448) that, during the early neonatal period, thyroid hormones control the synthesis of some nucleus-coded protein(s) involved in the assembly of F0,F1-ATPase.
A Almeida; C Lopez-Mediavilla; J M Medina
Related Documents :
822143 - Neonatal thyroid function in congenital hypothyroidism.
217853 - Simultaneous occurrence of hypopituitarism and adrenal medullary insufficiency in a boy...
1595633 - Electroencephalographic and behavioral-state studies in infants of cocaine-addicted mot...
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't    
Journal Detail:
Title:  Endocrinology     Volume:  138     ISSN:  0013-7227     ISO Abbreviation:  Endocrinology     Publication Date:  1997 Feb 
Date Detail:
Created Date:  1997-02-18     Completed Date:  1997-02-18     Revised Date:  2006-11-15    
Medline Journal Info:
Nlm Unique ID:  0375040     Medline TA:  Endocrinology     Country:  UNITED STATES    
Other Details:
Languages:  eng     Pagination:  764-70     Citation Subset:  AIM; IM    
Departamento de Bioquímica y Biología Molecular, Facultad de Farmacia, Universidad de Salamanca, Spain.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Adenosine Triphosphate / metabolism,  pharmacology
Animals, Newborn*
Hypothyroidism / chemically induced,  metabolism
Mitochondria, Liver / drug effects,  metabolism*
Mitochondrial Swelling / drug effects
Osmosis / drug effects*
Rats, Wistar
Thyroid Hormones / pharmacology*
Thyroxine / pharmacology
Triiodothyronine / pharmacology
Reg. No./Substance:
0/Thyroid Hormones; 56-65-5/Adenosine Triphosphate; 6893-02-3/Triiodothyronine; 7488-70-2/Thyroxine

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  Central lactogenic regulation of maternal behavior in rats: steroid dependence, hormone specificity,...
Next Document:  Induction of c-fos messenger ribonucleic acid in neuropeptide Y and growth hormone (GH)-releasing fa...