Abstract
The calcium accretion rate and the size of the exchangeable calcium pool was determined in rats between the 12th and 17th day of lactation after a single intraperitoneal injection of47Ca and85Sr. The serum specific activity and the retention of both radioactive isotopes in the whole body and tibia (shaft and ends) was determined. The single compartment kinetic model by Bauer was used for the analysis of data.
The results show a decrease in the accretion rate and an increase in the exchangeable calcium pool in lactating rats as compared to unmated animals.
Résumé
Le taux de dépôt du calcium et l'ampleur du calcium total échangeable sont déterminés chez le rat entre le 12ème et 17ème jour de lactation, après une injection intrapéritonéale unique de47Ca et85Sr. L'activité spécifique du sérum et la rétention des deux isotopes radioactifs dans l'organisme entier et le tibia (diaphyse et épiphyses) sont déterminées. L'analyse des résultats est réalisée à l'aide du modèle cinétique de Bauer à un compartiment unique. C'est ainsi qu'on observe une diminution du taux de dépôt et une augmentation du calcium total échangeable pendant la lactation.
Zusammenfassung
Die Geschwindigkeit der Calciumzunahme und die Größe des austauschbaren Calciumpools wurde bei Ratten zwischen dem 12. und 17. Tag der Lactation nach einer einmaligen intraperitonealen Injektion von47Ca und85Sr bestimmt. Die spezifische Aktivität beider radioaktiven Isotopen im Serum und ihre Retention im ganzen Körper und in der Tibia (Schaft und Epiphysen) wurden bestimmt. Das kinetische Modell von Bauer für ein Kompartiment wurde für die Datenanalyse verwendet.
Die Resultate zeigen eine Verminderung der Zunahmegeschwindigkeit und eine Erhöhung des austauschbaren Calciumpools bei laktierenden Tieren, verglichen mit unbegatteten Ratten.
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Blanuša, M., Harmut, M., Momčilović, B. et al. Kinetics of calcium metabolism in lactation. Calc. Tis Res. 7, 299–306 (1971). https://doi.org/10.1007/BF02062619
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DOI: https://doi.org/10.1007/BF02062619