title: The parallel effects of a very low molecular weight heparin (CY222) on anti Xa activity and thyroid hormone levels in blood.
abstract: A very low molecular weight heparin fragment (CY222) was administered by subcutaneous injection to a group of normal volunteers. This drug caused increased anti Xa activity with peak levels being observed two hours after injection. This coincided with changes in thyroid hormone levels especially with a fall in red cell thyroxine levels. Larger doses of CY222 caused a fall in serum total thyroxine and triiodothyronine, a rise in free thyroxine and a fall in TSH levels. It was thought that these findings may be due to the production of a circulating inhibitor of cellular uptake of thyroxine and that this might be related to the elevated levels of serum free fatty acids produced by the heparin.
mesh_terms: D005170:Factor X / Q000032:analysis* / Q000037:antagonists & inhibitors; D015951:Factor Xa; D006493:Heparin / Q000008:administration & dosage / Q000494:pharmacology*; D006801:Humans; D007279:Injections, Subcutaneous; D008297:Male; D013974:Thyroxine / Q000097:blood*; D014284:Triiodothyronine / Q000097:blood*
chemical_list: D014284:Triiodothyronine; D005170:Factor X; D006493:Heparin; D015951:Factor Xa; D013974:Thyroxine