Changes in Thyroid Function Associated With Pregnancy in Golden Hamsters
Date of Graduation
Master of Science in Biology
Thyroxine (T₄) and triiodothyronine (T₃) utilization rates were calculated to determine the changes in thyroid function during pregnancy in the hamster, (Mesocricetus auratus). Turnover rates were calculated via the plasma disappearance technique using ¹²⁵I-labeled hormones. Serum T₄ and T₃ were measured by RIA. Measurements were made before pregnancy and on gestational days 1, 7, and 13. The T₄ utilization increased (p < 0.05) tenfold during the latter part of pregnancy, apparently due to an elevated volume of T₄ distribution. Serum T₄ levels did not change. Triiodothyronine utilization did not change during pregnancy, but T₃ levels decreased middle to late pregnancy. A lower level of T₃ entering the tissues in the latter part of pregnancy seems to be an energy-conserving adaptation in this species.
© Lisa Harmon Walker
Walker, Lisa Harmon, "Changes in Thyroid Function Associated With Pregnancy in Golden Hamsters" (1992). MSU Graduate Theses. 194.