[Effect of dietary calcium during pregnancy and lactation on zinc levels in blood and bone, in rats].
The effect of dietary calcium (Ca) level on maternal zinc (Zn) nutritional status was studied. Female Wistar rats, weighing 250-350 g, were fed during pregnancy and lactation with an experimental diet containing/100 g different levels of calcium: 0.2 g (low calcium: LCa), 0.6 g (normal calcium: NCa) or 0.9 (high calcium: HCa). Maternal blood samples were drawn from the tail at delivery and at the end of lactation. Laboratory determinations were: Zn in whole blood (WB) at delivery and weaning; Zn (ZnF) and Ca (CaF) in the ashed femur at weaning. The results (mean +/- SEM) were: ZnWB (microgram/ml) at delivery and weaning: LCa: 8.73 +/- 1.05; 12.8 +/- 2.02; NCa: 3.49 +/- 0.19; 3.73 +/- 0.37; HCa: 3.21 +/- 0.19; 3.85 +/- 0.27. CaF (mg/100 mg): LCa: 19.2 +/- 0.8; NCa: 21.4 +/- 0.6; HCa: 20.4 +/- 1.1. ZnF (microgram/100 mg): LCa: 30.2 +/- 0.9; NCa: 24.1 +/- 0.3; HCa: 24.1 +/- 0.9. ZnWB was significantly higher in LCa (p < 0.0001) regarding NCa and Hca. ZnF showed an increase and CaF a decrease in LCa regarding NCa and HCa (p < 0.0001). There were no significant differences in ZnWB, ZnF and CaF between NCa and HCa These results show that: there was no detrimental effect when dietary Ca content was increased by 50% above the normal requirements of the rat.; low dietary Ca during pregnancy and lactation produced an increase of Zn utilization, reflected in maternal blood Zn and in ZnF content.
Weisstaub
Adriana
A
Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Hospital de Clínicas, Universidad de Buenos Aires, Buenos Aires, Argentina.
Zeni
Susana
S
de Ferrer
Patricia
P
de Portela
María Luz
ML
D000824:Animal Nutritional Physiological Phenomena; D000818:Animals; D002136:Calcium, Dietary / Q000008:administration & dosage*; D004032:Diet; D005260:Female; D005269:Femur / Q000737:chemistry / Q000378:metabolism*; D007774:Lactation / Q000378:metabolism; D008137:Longitudinal Studies; D011247:Pregnancy; D051381:Rats; D017208:Rats, Wistar; D015032:Zinc / Q000097:blood / Q000378:metabolism*
D002136:Calcium, Dietary; D015032:Zinc