Lactose synthesis and secretion by mammary epithelial cells in vitro, a comparative study

doi:10.1016/0300-9629(78)90106-8

Comparative Biochemistry and Physiology Part A: Physiology

Volume 61, Issue 2, 1978, Pages 253-259

Comparative Biochemi...

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Abstract

1.
1. A method is reported for studying lactose metabolism using dispersed mammary epithelial cells (MEC) in vitro.
2.
2. Lactose synthesis in the mouse was apparent during late pregnancy and continued throughout lactation. Rates of lactose synthesis and secretion and cell lactose contents were proportional to each other and were dependent upon the stage of lactation.
3.
3. Comparative analysis of dispersed MEC of other lactating animals revealed the following ranking of relative rates of lactose synthesis and secretion and of cell lactose contents: guinea pig, early lactation (EL) > rat, mid-lactation (ML) > rabbit (ML) = mouse (ML) > hamster (ML) > mouse (EL).
4.
4. Rates of lactose synthesis and secretion and cell lactose levels were proportional to the lactose concentration of each species' milk. In EL and ML mice, calculated Golgi secretory vacuole lactose concentrations closely approximated milk lactose levels.
5.
5. It is proposed that milk lactose levels are established by and are equivalent to the lactose concentrations of the primary fluid secretion of MEC, i.e. the fluid contents of the Golgi vacuole.

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Cited by (5)

Swelling of golgi vesicles in mammary secretory cells and its relation to the yield and quantitative composition of milk
1983, Journal of Theoretical Biology
A quantitative description is given of some cellular secretory mechanisms in the mammary epithelium, that can be used in the interpretation of changes in milk yield and composition. The volume of the aqueous phase is considered to depend on a flux of vesicles derived from the Golgi apparatus and on the degree of vesicle swelling prior to exocytosis. Milk proteins secreted by the Golgi route are diluted during vesicle swelling and secreted fat globules are diluted to their final, milk, concentration in the alveolar lumen. Swelling of Golgi vesicles is considered to occur through an osmotic flow of water induced by the intravesicular synthesis of lactose and by the net transport of ions coupled to lactose synthesis. A hypothetical model is given of ion transport mechanisms across the Golgi vesicle membrane to illustrate how the coupling of lactose synthesis to salt transport might occur.
Bioluminescent determination of lactose secretion: A measure of the in vitro performance of mammary acini from lactating rats
2002, Asian-Australasian Journal of Animal Sciences
The study of differentiative potential of the lactating mouse mammary gland in organ culture
1984, In Vitro
Morphology and lactose synthesis in tissue culture of mammary alveoli isolated from lactating mice
1982, In Vitro - Plant
A putative role for cell-cell epithelial contacts in lactose secretion
1979, The Japanese Journal of Physiology

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Lactose synthesis and secretion by mammary epithelial cells in vitro, a comparative study

Abstract

J. biol. Chem.

Biochem. biophys. Res. Commun.

Cell Differentiation

Comp. Biochem. Physiol.

Archs Biochem. Biophys.

J. Dairy Sci.

Secretion of α-lactalbumin into milk and its relevance to the organization and control of lactose synthesis

Nature, Lond.

The lactose synthetase particles of lactating bovine mammary gland: preparation of particles with intact lactose synthetase

Biochem. J.

The lactose synthetase particles of lactating bovine mammary gland: characteristics of the particles

Biochem. J.

High resolution autoradiographic study of normal lactating mammary gland and mammary tumors of the mouse: preliminary report

J. natn. Cancer Inst.

Technique for mammary epithelial cell isolation and cultivation

A lactation curve for mice

Lab. Anim. Care

Quantitative electron microscopy of subcellular organization in mammary gland cells before and after parturition

Cytology and fine structure of the mammary gland

Morphology of secretion in mammary gland cells