S-100 and glial fibrillary acidic (GFAP) proteins: immunohistochemical markers of the folliculo-stellate cells of the Lagostomus maximus maximus pituitary.

ACOSTA, MARIANO; FILIPPA, VERÓNICA; MOHAMED, FABIAN

Tandil, Buenos Aires

Congreso; X Congreso Argentino de Ciencias Morfológicas; 2006

Sociedad Argentina de Ciencias Morfológicas

Immunohistochemical techniques has enabling to extend the morphological study of the folliculo-stellate (FS) cells. The pituitary gland of viscacha (Lagostomus maximus maximus) exhibits follicular structures formed by FS cell. The aim of this work was to immunohistochemically identify FS cells of pituitary gland using anti-S-100 and anti-GFAP antisera. Moreover, lanthanum hydroxide was used as intercellular marker. Pituitary glands of adult male viscachas were processed for light and electronic microscopy. The immunolabeling pattern of the S-100 was nuclear and cytoplasmic and cytoplasmic for GFAP. FS cells were present in the pars intermedia and pars distalis of pituitary gland. They were spread around pituitary follicles and their cytoplasmatic processes were found between neighboring endocrine cells. The tracer penetrated freely into the intercellular spaces, delineating the cellular borders of granulated and nongranulated cells. These results suggest the FS cells probably participate in a network of intrahypophyseal communication and may be involved in the modulation of the adenohypophyseal endocrine activity. The expression of S-100 and GFAP suggest of neuroectodermal origin of the FS cell of viscacha pituitary gland.