Seasonal Changes of Triiodothyronine Binding to Piscine Ovarian Nuclei : Endocrinology

概要

論文の詳細を見る
The pattern of ^125<I>-triiodothyronine (^125<I>-T_3) binding to the fairly pure oocytes nuclei preparation and plasma T_3 levels were studied in the seasonally breeding fresh water perch, Anabas testudineus. ^125<I>-T_3 binding affinity was found to remain fairly constant (Ka varied from 0.11 to 0.12 × 10^9 M^<-1>) during the four reproductive phases while maximum binding capacity (MBC) altered significantly. The highest value was seen in the prespawning phase (MBC = 4.13 p mole/mg DNA) and the lowest in postspawning phase (MBC = 3.44 p mole/mg DNA). Plasma T_3 level was in a peak during prespawning (2.9ng/ml) whereas it was the lowest in postspawning phase fish (0.92ng/ml). Seasonal indices of plasma T_3 level and MBC suggest an autoregulation of T_3 binding site. Further evidences in support of this were obtained from fish treated with T_3, thiourea and thiouracil; T_3 increased ^125<I>-T_3 binding while antithyroid drugs decreased it significantly.
社団法人日本動物学会の論文
1989-08-15