Circulating Thyroid Hormones in Primates with Mild or Severe Hepatitis Following Liver Transplantation

Summary

In order to study the effects of acute immunologically mediated liver disease on circulating thyroid hormones, serum levels of thyroxine (T₄, total and free) and triiodothyronine (T₃) were measured in 8 baboons before and for 60 days after allogeneic liver transplantation. In 3 animals early rejection and jaundice developed; T₄ levels declined as liver function deteriorated. In the 5 tolerant animals liver function was only temporarily deranged without jaundice and there was a consistant early rise in T₄ (P < 0.01) followed by a later fall. T₃ concentrations were relatively normal in both groups. The T₃ resin uptake test remained virtually unchanged in all animals. Serum T₄ and T₃ responses to exogenously administered bovine thyrotropin (TSH) were similar in the jaundiced and anicteric animals. We conclude that the early rise in T₄ in the tolerant animals was caused by transient increases in thyroid binding globulin in (TBG) while the fall in thyroid hormones in these and in the jaundiced animals was related to a decline in TBG levels. Thyroid responsiveness to TSH is not disturbed by moderately deranged liver function.

Key-Words

Thyroxine - Triiodothyronine - Liver Transplantation - Jaundice