Thyroid control of sarcolemmal Na+/Ca2+ exchanger and SR Ca2+-ATPase in developing rat heart
Jazyk angličtina Země Spojené státy americké Médium print
Typ dokumentu časopisecké články, práce podpořená grantem
- MeSH
- Ca2+-ATPasy biosyntéza MeSH
- genetická transkripce účinky léků MeSH
- hypertyreóza chemicky indukované metabolismus patofyziologie MeSH
- hypotyreóza chemicky indukované metabolismus patofyziologie MeSH
- krysa rodu Rattus MeSH
- membránové proteiny metabolismus MeSH
- messenger RNA biosyntéza MeSH
- myokard metabolismus MeSH
- novorozená zvířata MeSH
- potkani Wistar MeSH
- propylthiouracil farmakologie MeSH
- proteiny vázající vápník biosyntéza MeSH
- pumpa pro výměnu sodíku a vápníku biosyntéza MeSH
- regresní analýza MeSH
- sarkolema metabolismus MeSH
- sarkoplazmatické retikulum enzymologie MeSH
- srdce růst a vývoj MeSH
- štítná žláza fyziologie MeSH
- trijodthyronin farmakologie MeSH
- vývojová regulace genové exprese * účinky léků MeSH
- zvířata MeSH
- Check Tag
- krysa rodu Rattus MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- Ca2+-ATPasy MeSH
- membránové proteiny MeSH
- messenger RNA MeSH
- phospholamban MeSH Prohlížeč
- propylthiouracil MeSH
- proteiny vázající vápník MeSH
- pumpa pro výměnu sodíku a vápníku MeSH
- trijodthyronin MeSH
Thyroid hormone (TH) levels increase in the postnatal life and are essential for maturation of myocardial Ca2+ handling. During this time, the sarcolemmal (SL) Na+/Ca2+ exchanger (NCX) function decreases and the sarcoendoplasmic reticulum (SR) Ca2+-ATPase (SERCA2) function increases. We examined the effects of postnatal hypo- or hyperthyroidism on NCX and SERCA2 in rat hearts. Animals were rendered hypothyroid by 0.05% 6-n-propyl-2-thiouracil in drinking water given to nursing mothers from days 2 to 21 postpartum. Hyperthyroidism was induced by daily injections of 10 microg/100 g body weight of 3,3',5-triiodo-L-thyronine during this period. Ventricular steady-state mRNA and protein levels of NCX and SERCA2 were analyzed by Northern and Western blotting. These were compared with SL Na+ gradient-induced and SR oxalate-supported Ca2+ transports in isolated membranes. In hypothyroidism, NCX mRNA and protein were elevated by 66 and 80%, respectively, and SERCA2 mRNA and protein were reduced to 55 and 70%, respectively (P < 0.05 vs. euthyroid). Corresponding differences were observed in the respective Ca2+ transports. Conversely, reduced NCX (by 50%) and elevated SERCA2 (by 150%) activities were found in hyperthyroidism (P < 0.05). The levels of NCX and SERCA2 mRNA and protein were, however, unchanged in hyperthyroidism, indicating that functional changes are not due to altered NCX and SERCA2 expression. In this case, a decline in noninhibitory phosphorylated phospholamban is a likely explanation for the elevated SR Ca2+ transport. In conclusion, physiological TH levels appear to be essential for normal reciprocal changes in the expression and function of myocardial NCX and SERCA2 during postnatal development.
Citace poskytuje Crossref.org
Sixty Years of Heart Research in the Institute of Physiology of the Czech Academy of Sciences
Effect of hypo- and hyperthyroid states on phospholipid composition in developing rat heart
