ISSN:
1432-0878
Keywords:
Anterior pituitary
;
Corticotropes
;
α-MSH
;
Immunocytochemistry
;
Rat
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Medicine
Notes:
Summary Specific antisera to α-melanotropin (α-MSH) and corticotropin (ACTH 1-39) were used to obtain immunocytochemical evidence for the differential localization of α-MSH and ACTH in the secretory granules of corticotropes of rat anterior pituitary. The specificity of the antisera was established by binding 131I-labeled α-MSH and ACTH 1-39 to their respective antisera. Double-labeling immunocytochemistry (for α-MSH, ferritin; for ACTH, colloidal gold) was performed. Some secretory granules were labeled with ferritin particles (α-MSH), whereas others contained gold particles (ACTH). Only a few granules showed both ACTH and α-MSH. In typical corticotropes (stellate in form with a small number of secretory granules aligned along the cell periphery) only some of the secretory granules that were labeled with anti-ACTH serum were also immunoreactive to anti-α-MSH. In atypical corticotropes (polygonal in shape and containing a large number of secretory granules) almost all of the immunoreactive ACTH secretory granules were also positive to anti-α-MSH serum. An intermediate type of corticotrope was observed containing a small number of secretory granules, almost all of which were labeled with anti-α-MSH. Thus, rat anterior pituitary corticotropes may be classified into three types according to the distribution and content of α-MSH. The light-microscopic immuncytochemistry provided similar results.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00251036
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