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. 2008 May 5;13(4):514–525. doi: 10.2478/s11658-008-0020-y

Calcium transport by mammary secretory cells: Mechanisms underlying transepithelial movement

David B Shennan 1,✉
PMCID: PMC6275681  PMID: 18458827

Abstract

The secretion of calcium into milk by mammary epithelial cells is a fundamentally important process. Despite this, the mechanisms which underlie the movement of calcium across the lactating mammary gland are still poorly understood. There are, however, two models which describe the handling of calcium by mammary epithelial cells. On the one hand, a model which has existed for several decades, suggests that the vast majority of calcium enters milk via the Golgi secretory vesicle route. On the other hand, a new model has recently been proposed which implies that the active transport of calcium across the apical membrane of mammary secretory cells is central to milk calcium secretion. This short review examines the strengths and weaknesses of both models and suggests some experiments which could add to our understanding of mammary calcium transport.

Key words: Calcium, Mammary, Secretion

Full Text

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Abbreviations used

PMCA

plasma membrane calcium-ATPase

SERCA

sarco/endoplasmic reticulum calcium-ATPase

SPCA

secretory pathway calcium-ATPase

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