Effect of thyroid hormones on postnatal fibrinogen levels in the rat

From normal adult values of about 2.4 g/l at birth, rat plasma fibrinogen levels decrease to a minimum between 10 and 30 days of age and increase again at the end of weaning. The values of fibrinogenemia measured with different methods (heat precipitation at 56 degrees C versus clotting time) disagree. These results are discussed in connection with the development of the hypothalamic-pituitary-thyroid axis.