[Pregnancy-associated molecular variation of thyroxine-binding globulin in health and in various diseases of man].
A molecular variant of human serum thyroxine-binding globulin (TBG), containing only triantennary oligosaccharide chains and having a more prolonged in vivo survival (TBG-1), was first detected in normal pregnancy and then in the postpartum period. Serum TBG-1 was measured in normal and in some pathological conditions associated with normal or increased TBG biosynthesis using a combination of Con A-Sepharose 4B microcolumn affinity chromatography and a highly sensitive TBG radioimmunoassay. TBG-1 was shown to be present in the sera of healthy subjects (0.21 +/- 0.04 micrograms/ml, n = 60; 1.15% of total TBG). The proportion of TBG-1 in total serum TBG was significantly increased (up to 9.5%) in conditions with serum TBG excess (cancer, hypothyroidism and liver diseases). It has been assumed that a selective enhancement of biosynthesis of the TBG molecular variant with a prolonged half-life in the circulation during the posttranslational modification of the polypeptide chain is a response to the body requirements in a high TBG concentration.
Kiseleva
E E
EE
Ermolenko
M N
MN
Shitikov
B D
BD
Kosheleva
M I
MI
Sviridov
O V
OV
Strel'chenok
O A
OA
D005260:Female; D006207:Half-Life; D006801:Humans; D008297:Male; D011247:Pregnancy / Q000097:blood*; D011248:Pregnancy Complications / Q000097:blood*; D011499:Protein Processing, Post-Translational / Q000502:physiology; D012016:Reference Values; D013975:Thyroxine-Binding Proteins / Q000737:chemistry* / Q000378:metabolism
D013975:Thyroxine-Binding Proteins
Sviazannaia s beremennost'iu molekuliarnaia raznovidnost' tiroksinsviazyvaiushchego globulina v norme i pri nekotorykh zabolevaniiakh u cheloveka.