Androgenic expression in the submandibular gland of zinc-deficient mice.
The effects of zinc deficiency were studied in mice submandibular salivary glands (SMG). Zn-restricted mice (Zn-) were maintained from weaning until adult age (60 days) with a powdered diet containing 3 mg Zn2+/kg. Pair-fed animals (30 mg Zn2+/kg powdered diet) and control animals fed a regular pelleted diet were also used. Total protein content and proteolytic activity of SMG did not differ among the groups, but morphometric evaluations revealed significant alterations in the nucleus/cytoplasm size ratios, most likely due to an absolute reduction in nuclear volume (control = 122.5 +/- 6.4; Zn- = 91.6 +/- 10.5; pair-fed = 125.1 +/- 6.8 microns 3) paralleled by an increase of the height of the duct epithelium (control = 70.5 +/- 3.0; Zn- = 90.5 +/- 4.2; pair-fed = 81.7 +/- 3.0 microns). The altered food consistency could be responsible for these morphological changes. In order to assess the subcellular distribution of SMG androgen receptors in conditions of chronic Zn deficiency, Zn- animals were mated and the F1 generation was fed as their dams until the age of 45 days. Cytosolic (in 105,000 g supernatants) and nuclear (KCl-extracted) SMG receptors were determined with [3H]R1881. The Zn- animals had reduced nuclear/cytosolic ratios of androgen receptors (control = 0.62; Zn- = 0.14), as an indication that chronically deficient Zn intake determines a sort of destabilization of the interactions of androgen-receptor complexes with target cell nucleus.
Minetti
C A
CA
Department of Histology/Embryology, Universidade de São Paulo, Brazil.
Oshiro
M M
MM
Santos
M F
MF
Romaldini
J H
JH
Moura
N M
NM
Valle
L B
LB
Oliveira-Filho
R M
RM
D000728:Androgens / Q000378:metabolism*; D000818:Animals; D002467:Cell Nucleus / Q000378:metabolism / Q000648:ultrastructure; D003593:Cytoplasm / Q000378:metabolism / Q000648:ultrastructure; D005243:Feces / Q000737:chemistry; D005260:Female; D008297:Male; D051379:Mice; D009929:Organ Size; D011944:Receptors, Androgen / Q000378:metabolism; D013363:Submandibular Gland / Q000378:metabolism* / Q000473:pathology; D013739:Testosterone / Q000097:blood; D015032:Zinc / Q000172:deficiency*
D000728:Androgens; D011944:Receptors, Androgen; D013739:Testosterone; D015032:Zinc