Abstract
The nature of thyroid hormone uptake into the cell and the possible involvement of the serum carrier proteins and receptor-mediated endocytosis in this process are reviewed. The evidence that there is a specific thyroid hormone-binding receptor in the inner mitochondrial membrane and the relation of this to the adenine nucleotide translocator is discussed. Direct effects of thyroid hormone on mitochondrial function that might be mediated by such a receptor are also considered