Table 5: Potency and Efficacy for Compounds Identified in the NTP Library Screening.

Agonists Potency, µM Efficacy, %
13-cis-retinal 7.1 11.8
trans-retinal 14.9 11.4
Antagonists
5-fluorouracil 6.7 -86.7
1-acetyl-2-phenylhydrazine 10.6 -87.5

Potency (EC50 and IC50) values were calculated from full dose response curves in the absence and presence of T3 (1nM), respectively. Efficacy was defined as percentage of maximal induction (agonist mode) or inhibition (antagonist mode) relative to T3 set at 100% (100 nM for testing of agonist and 1 nM for antagonist activity).