suppressive effect on pituitary TSH secretion (9). They also found that it was much more potent than T4 (10), although it was less abundant than T4 in the thyroid gland (11). Based on these findings Gross and Pitt-Rivers hypothesized that T3 was the active peripheral thyroid hormone and T4 was its precursor.
(Photo: Tom Tingle/The Republic) U.S. Sen. Jeff Flake may have a long two years ahead of him. Up for re-election in 2018, the first-term Arizona Republican is already under attack from the right and the left.
Jeff Flake in danger of being primaried. Veteran GOP operative Jim Ellis points to the second poll so far this cycle showing Flake in big trouble â not of losing to a Democrat, but of losing his primary. Neither poll is particularly impressive in its pedigree, but the idea that Flake is in trouble is by no means far-fetched.