Abstract
1. Injection of citrate or EGTA solutions into the lumen of the mammary gland of goats in quantities sufficient to reduce ionized calcium to less than one-tenth of normal, led to increases in milk concentrations of Na and Cl and decreases in K and lactose. 2. Subsequent milk yields were decreased in glands treated with citrate but not in those treated with EGTA. 3. Blood-milk potential difference decreased (i.e. towards zero) in glands in which citrate was present. 4. In goats milked hourly with the aid of oxytocin, milk Na and Cl concentrations increased while K and lactose decreased; there was no apparent decrease in Ca2+ concentration. 5. It is suggested that ionized calcium in milk is essential to preserve the integrity of the mammary epithelium during lactation.
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Selected References
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- Amsterdam A., Jamieson J. D. Studies on dispersed pancreatic exocrine cells. I. Dissociation technique and morphologic characteristics of separated cells. J Cell Biol. 1974 Dec;63(3):1037–1056. doi: 10.1083/jcb.63.3.1037. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Fleet I. R., Linzell J. L., Peaker M. The use of an autoanalyzer for the rapid analysis of milk constituents affected by subclinical mastitis. Br Vet J. 1972 Jun;128(6):297–300. doi: 10.1016/s0007-1935(17)36934-8. [DOI] [PubMed] [Google Scholar]
- Galli P., Brenna A., Camilli de P., Meldolesi J. Extracellular calcium and the organization of tight junctions in pancreatic acinar cells. Exp Cell Res. 1976 Apr;99(1):178–183. doi: 10.1016/0014-4827(76)90694-7. [DOI] [PubMed] [Google Scholar]
- Holt C., Muir D. D. Inorganic constituents of milk: I. Correlation of soluble calcium with citrate in bovine milk. J Dairy Res. 1979 Jul;46(3):433–439. doi: 10.1017/s0022029900017465. [DOI] [PubMed] [Google Scholar]
- LINZELL J. L. Mammary-gland blood flow and oxygen, glucose and volatile fatty acid uptake in the conscious goat. J Physiol. 1960 Oct;153:492–509. doi: 10.1113/jphysiol.1960.sp006550. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Linzell J. L., Mepham T. B., Peaker M. The secretion of citrate into milk. J Physiol. 1976 Sep;260(3):739–750. doi: 10.1113/jphysiol.1976.sp011541. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Linzell J. L., Peaker M. Day-to-day variations in milk composition in the goat and cow as a guide to the detection of subclinical mastitis. Br Vet J. 1972 Jun;128(6):284–295. doi: 10.1016/s0007-1935(17)36932-4. [DOI] [PubMed] [Google Scholar]
- Neville M. C., Peaker M. The secretion of calcium and phosphorus into milk. J Physiol. 1979 May;290(2):59–67. doi: 10.1113/jphysiol.1979.sp012759. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Peaker M. Mechanism of milk secretion: milk composition in relation to potential difference across the mammary epithelium. J Physiol. 1977 Sep;270(2):489–505. doi: 10.1113/jphysiol.1977.sp011964. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Peaker M. The effect of raised intramammary pressure on mammary function in the goat in relation to the cessation of lactation. J Physiol. 1980 Apr;301:415–428. doi: 10.1113/jphysiol.1980.sp013214. [DOI] [PMC free article] [PubMed] [Google Scholar]