ISSN:
1432-0878
Keywords:
Cell determination
;
ACTH cells
;
LH cells
;
Organ culture
;
Immunohistochemistry
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Medicine
Notes:
Summary In fetal rats, immunoreactive ACTH and LH cells are known to appear first near the ventral periphery of the pars distalis. The objective of this study was to test whether the developmental fate of these types of cells is actually determined in the ventral region of the developing adenohypophysis. Before the appearance of any immunoreactive cells (days 12.5–13.5), the adenohypophysial primordia of fetal rats were cut at different levels into dorsal and ventral parts and were then cultivated with surrounding tissues. When separated on day 12.5, ACTH and LH cells were immunohistochemically demonstrated almost exclusively in expiants of the dorsal half. Furthermore, a considerable number of ACTH and LH cells were found even in cultures of the most dorsal small region, i.e., the primordial roof accompanied by the brain. Cultivation of “roofless” primordia on the other hand, resulted in a marked decrease in the number of both types of cells. When adenohypophysial primordia were isolated and cut on day 13.5, a number of ACTH cells were observed alike in expiants of both the dorsal and ventral halves. On the other hand, LH cells were found almost exclusively in those expiants derived from the ventral half. The fact that the majority of future LH cells were included within the ventral bulgings called the lateral lobes was also shown either by their cultivation or removal. These results suggest that the developmental fate of ACTH and LH cells is determined in the dorsal region. A possible change in the localization of such determined cells from the dorsal to ventral portion of the pars distalis is discussed in relation to adenohypophysial growth during development.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00210885
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