Mammary gland function and development: effect of zinc deficiency in rat

Abstract

The effect of dietary zinc deficiency during late pregnancy and lactation on the rat mammary gland was investigated by feeding female rats either a zinc-deficient diet (0.4 ppm Zn) or a zinc-sufficient diet (100 ppm Zn) ad libitum or restricted in amount. Zinc deficiency from day 0 of lactation specifically reduced the total RNA content of lactating mammary glands on day 14, but had no effect beyond that of food restriction on their total DNA content, Both RNA and DNA content of the mammary gland were decreased by reduced food intake. Zinc deficiency from day 14 of pregnancy to day 2 of lactation severely impaired parturition and prevented the normal rise in mammary gland RNA seen during lactogenesis in control animals. A shorter deficiency period, from day 18 of gestation, had no effect on mammary gland nucleic acids other than that due to inanition.

Essential Role for Zinc Transporter 2 (ZnT2)-mediated Zinc Transport in Mammary Gland Development and Function during Lactation

“…Collectively, the loss of ZnT2 resulted in mammary gland hypoplasia, the underlying cause of failed lactogenesis II where the mother is unable to produce an adequate milk volume (79). The etiology of breast hypoplasia is unknown, but our observations along with previous studies regarding zinc deficiency and the mammary gland (3)(4)(5) suggest that tight regulation of zinc metabolism plays an important role in regulating mammary gland biology.…”

Zinc Signaling in the Mammary Gland: For Better and for Worse

“…The importance of Zn 2+ to mammary gland development is manifested by the severe consequences of Zn 2+ deficiency. Under these conditions, extreme defects in morphology and function, including oxidative stress and inflammation, are described in the non-lactating [ 63 , 64 ] as well as in the lactating gland [ 65 ]. During puberty, growth and differentiation of the epithelial glandular structures within the fat pad are driven by the growth hormones, EGF and IGF-1, as well as by the estrogen receptor [ 66 ].…”

Gestational Zinc Deprivation in Mice: Persistence of Immunodeficiency for Three Generations

“…The PFC response to SRBC's and the concentration of immunoglobulin M (IgM) in serum were assessed in some offspring at 6 weeks, 10 weeks, and 6 months, of age; the retnainder of the offspring were mated (brothers to sisters) at 10 weeks of age to produce an F2 generation. Because a consequence of zinc deprivation during pregnancy is impaired development of the mammary gland and reduced la6tational ability (12), pups from zinc-deprived dams were cross-fostered to control dams and pups from control dams were, cross-fostered to zinc-deficient dams. The F2 and F3 offspring were culled to five pups and studied at thq same ages as the F, offspring or bred at 10 weeks of age.…”