Cystlike structures derived from the marginal cells of Rathke's cleft in XXXX pituitary grafts.

@entity35 @entity39
Hemipituitary glands from 30 @entity35 were isotransplanted under renal capsules. At 1, 2, 4, 7 and 20 days after transplantation, the grafts were examined by light and electron microscopy. Two days after transplantation, the central area of graft showed @entity39 ; however, the peripheral area, where marginal cells of Rathke's cleft were ingesting the remnants of @entity39 glandular cells, survived. Four days after transplantation, mitotic figures of marginal cells were observed. Seven days after transplantation, the damaged area of the graft disappeared, and Rathke's cleft was completely lined by marginal cells. Remnants of @entity39 glandular cells were not seen in intercellular spaces or in the cytoplasm of marginal cells. Cystlike structures formed in the grafts; some were connected to Rathke's cleft by narrow cavities. The cavity-lining cells of the cysts were agranular and similar to those that lined Rathke's cleft. At 20 days after transplantation, granular cavity-lining cells appeared. It is suggested that marginal cells of immature @entity35 can differentiate into granular cells.
