The interaction of 1-anilino-8-naphthalenesulfonate with thyroid lipids and membranes: a nuclear magnetic resonance study.

The proton magnetic resonance (PMR) spectra of thyroid cell membranes and their total lipid extracts, in the presence of 1-anilino-8-naphthalenesulfonate (ANS), have been studied. The addition of ANS causes an shifting of the head group PMR signal, a splitting of the signal into two components and an increase in total spectral intensity. The data suggest that ANS interacts with phospholipid in the membrane as it does in total lipid vesicles. Evidence is also presented for the removal of lipids from the membrane, by ANS, and the subsequent formation of micelles. The membrane results are compared with our earlier work on the interaction of ANS with egg phosphatidylcholine (P.C.) vesicles and the results are used in explaining the inhibition of iodide transport in isolated thyroid slices.