Effect of L-thyroxine (LT4) and D-thyroxine (DT4) on cardiac function and high-energy phosphate metabolism: a 31P NMR study.
31P NMR spectroscopy was used to monitor the cardiac energy metabolism in hypothyroid rat hearts. Differential alterations in phosphocreatine and inorganic phosphate levels were observed upon treatment of hypothyroid animals with DT4 and LT4, while both agents were equipotent in reducing cholesterol. These results show potential for NMR spectroscopy as a technique to determine therapeutic selectivity.
Sandhu
G S
GS
Research Department Pharma Division, CIBA-GEIGY Corporation, Summit, New Jersey 07901.
Steele
R
R
Gonnella
N C
NC
D000255:Adenosine Triphosphate / Q000032:analysis; D000818:Animals; D000924:Anticholesteremic Agents / Q000627:therapeutic use*; D002784:Cholesterol / Q000097:blood; D003918:Dextrothyroxine / Q000627:therapeutic use*; D004734:Energy Metabolism; D006321:Heart / Q000187:drug effects*; D007037:Hypothyroidism / Q000175:diagnosis / Q000188:drug therapy*; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D009206:Myocardium / Q000378:metabolism*; D010710:Phosphates / Q000378:metabolism*; D010725:Phosphocreatine / Q000032:analysis; D051381:Rats; D011919:Rats, Inbred Strains; D013974:Thyroxine / Q000627:therapeutic use*
D000924:Anticholesteremic Agents; D010710:Phosphates; D010725:Phosphocreatine; D003918:Dextrothyroxine; D000255:Adenosine Triphosphate; D002784:Cholesterol; D013974:Thyroxine