ISSN:
1432-0878
Keywords:
Mammary gland
;
Growth inhibitor
;
Epithelium
;
Cell types
;
Differentiation
;
Immunocytochemistry
;
Immunohistochemistry
;
Cow
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Medicine
Notes:
Abstract Localization of a mammary-derived growth inhibitor (MDGI) in the bovine mammary gland was verified by light-and electron-microscopic methods. Expression of MDGI, which is known to inhibit the growth of mammary epithelial cell lines in vitro, was found to be highest in the late pregnant and in the lactating state. A combination of immunohistochemical and immunocytochemical methods with semi- and ultrathin resin sections revealed marked variations in MDGI staining. High MDGI levels were predominantly detectable in epithelial cells with large milk fat droplets. Distinct cell types that were almost free of label could be identified among bovine mammary epithelial cells that always exhibited high MDGI levels. Similar results were obtained when using a serum-free organ culture system in which MDGI was hormonally induced in cell types of comparable differentiation state. The specific occurrence of the growth inhibitor in developing alveoli and certain cell types points to the association between MDGI expression and functional differentiation in the normal mammary gland.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00302743
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