Résumé
Metallothionein (MT) family, intracellular zinc binding proteins, has been suggested to play an important regulatory role in zinc metabolism. The present study utilized light and confocal microscopic methods to investigate the expression pattern of MT-1, 2 and to determine the distribution and extent of colocalization of MT-1, 2 relative to subpopulations of S100 positive folliculostellate (FS) cells and somatotrophs in normal rat anterior pituitary. By light microscopy, MT-1, 2 immunoreactivity was observed both in pars intermedia and pars distalis of anterior pituitary. Confocal microscopy revealed that most MT immunoreactivity was colocalized in S100 positive FS cells, not in somatotrophs. This is the first report that FS cells in pars distalis contain MT-1, 2. These results suggest that MT family may be involved in regulation of hypophyseal endocrine functions and can be used as new markers of FS cells.