REGULATION OF NA-ATPASE IN SUBMANDIBULAR GLANDS OF HYPOPHYSECTOMIZED MALE-MICE BY STEROID AND THYROID-HORMONES(,K+)

Citation
K. Kurihara et al., REGULATION OF NA-ATPASE IN SUBMANDIBULAR GLANDS OF HYPOPHYSECTOMIZED MALE-MICE BY STEROID AND THYROID-HORMONES(,K+), The Journal of histochemistry and cytochemistry, 44(7), 1996, pp. 703-711
Citations number
44
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Cell Biology
ISSN journal
0022-1554
Volume
44
Issue
7
Year of publication
1996
Pages
703 - 711
Database
ISI
SICI code
0022-1554(1996)44:7<703:RONISG>2.0.ZU;2-N
Abstract
The effects of thyroid hormone, androgen, glucocorticoid, and mineralo corticoid on Na+,K+-ATPase activity and on levels of its alpha-subunit protein (alpha 1 isoform) in mouse submandibular gland (SMG) were stu died by enzyme assay for ouabain-sensitive ATP hydrolysis, by quantita tive densitometric scanning of Western blots, and by immunohistochemis try. To define the specific regulatory effects of various pituitary-de pendent hormones on expression of Na+,K+-ATPase in the SMG, we treated hypophysectomized (hyper) male mice with triiodo-L-thyronine (T-3), 5 alpha-dihydrotestosterone (DHT), dexamethasone (Der), and aldosterone (Aid), injected singly or in combination, Na+,K+-ATPase was confined to the duct system of the SMG, Zn intact mice there was a gender diffe rence in SMG Na+,K+-ATPase, with levels of the enzyme's activity and o f its al-subunit being less in the glands of males. In males, hypophys ectomy caused a rise in levels of Na+,K+-ATPase activity and in levels of the alpha 1-subunit protein of this enzyme, and in intensity of im munocytochemical staining for this subunit but there were no such chan ges in the SMG of hyper females, Changes caused by hormonal replacemen t to hyper males in Na+,K+-ATPase activity, levels of its alpha 1-subu nit, or the intensity of immunocytochemical staining for this subunit were complex. Aid had no effect, T-3 or dexamethasone, given alone, in duced Na+,K+-ATPase activity above control values (hypox males) and in creased levels of its alpha 1-subunit protein and immunohistochemical staining for this subunit, By contrast, DHT did not cause a decline in any of these parameters. However, when treatment with T-3 was combine d with administration of Der or DHT, enzymatic activity of Na+,K+-ATPa se decreased but levels of the alpha 1-subunit protein and immunohisto chemical staining for this subunit increased. Therefore, inductions of the alpha 1-subunit of this enzyme are not always correlated with inc reases in levels of activity of Na+,K+-ATPase, and we propose that bot h enzymatic and immunochemical analyses are essential for evaluation o f hormonal regulation of Na+,K+-ATPase in salivary gland and in other tissues.