Further studies on the antigoitrogenic action of iodoarachidonates.

Previous studies have shown that iodoarachidonates (IAs) prevent goiter production in rats. In the present studies we show that both IL-d and IL-w (IAs bearing the iodine atom at the positions 6 and 14, respectively), cause a significant involution of preformed goiter. This effect was evident when IAs were administered either orally or via i.p., although the first one required larger doses to obtain the same degree of inhibition. No changes were observed in serum protein, urea, cholesterol, cholinesterase, T3 or T4. In vitro studies with FRTL-5 cells showed that both IAs inhibit iodide and alpha-AIB uptake, as well as ATPase activity.