Differential effects of propylthiouracil (PTU), methimazole (MMI) and thyroidectomy (Tx) on liver and plasma proteins have been studied in rats, some of which have been simultaneously treated with L-thyroxine (T4). Although the absolute liver weights were lower in all hypothyroid groups, the relative liver weights (g/100 g) were significantly higher in PTU and MMI groups, while in Tx group they were lower. T4 administration raised the absolute liver weights in all groups, even though there was no significant difference between relative weights in PTU and MMI groups. In Tx group, however, the relative weight was restored to control level. One of the constituents responsible for the increased relative liver weight was liver protein. The increased liver protein concentration (mg/g) was, however, not reflected in the synthesis rate which was uniformly low in all groups inspite of T4 therapy. Plasma albumin concentration was raised in hypothyroid rats which did not respond to T4 therapy. On the other hand, increased total plasma protein level was restored to normal. Relative 14C-glycine incorporation into albumin, fibrinogen, seromucoids and total proteins was reduced from 14 to 30%, 5.2 to 19% and 13 to 23% of control in PTU, MMI and Tx groups, respectively. Of these, only MMI and Tx groups appeared to be responsive to T4 therapy. Of all the protein fractions, fibrinogen synthesis was least affected by various treatments. To some extent these observations may be explained on the basis of altered general endocrine status and specific extra-thyroidal effects, rather than on the basis of thyroid status alone.
Serum ferritin, one of the nonspecific tumor markers, was studied in 102 thyroid cancer patients, who had been thyroidectomized and were off thyroxine for 1 month, making them hypothyroid. Serum ferritin in thyroid cancer patients was not significantly different as compared to controls. Nevertheless, high levels of serum ferritin were observed in the thyroid cancer group as compared to primary hypothyroid patients. Furthermore, there was a significant difference in serum ferritin between thyroid cancer patients without metastasis and those with metastasis, patients with metastasis showing higher levels. Classification of thyroid cancer patients into different histological types revealed higher ferritin levels in follicular carcinoma as compared to papillary carcinoma. These data suggest that, although serum ferritin may not be a tumor marker for thyroid cancer, this parameter seems to be sensitive to the presence of metastasis and the histologic diagnosis.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.