Submitted to: Journal of Federation of American Societies for Experimental Biology
Publication Type: Abstract Only
Publication Acceptance Date: 1/31/2008
Publication Date: 4/15/2008
Citation: Hunt, C., Stoecker, B.J. 2008. Adequate dietary calcium restores vertebral trabecular bone microarchitecture and strength and improves femur calcium concentration following calcium depletion in young female rats. [abstract] Journal of Federation of American Societies for Experimental Biology. 22:883.1.
Technical Abstract: To determine whether dietary calcium deficiency during adolescence permanently reduces lifetime potential to attain peak bone mass and strength, female Sprague-Dawley rats were separated into groups (n=10) and fed an AIN-93G-based diet containing 20% (1000 mg Ca/kg) of the calcium requirement from weaning until 105 d of age (DEF); switched near sexual maturity (63 d of age) to 100% of the requirement (5000 mg Ca/kg) (RP); or pairfed (5000 mg Ca/kg) throughout to group RP (PF). At 105 d of age, Ca repletion restored L4 trabecular bone volume fraction (RP: 27.0 ± 1.1%; PF: 28.1 ± 1.2%; p = 0.46) and strength (estimated by force to compression with finite element analysis) (RP: 11.51 ± 0.87 N; PF: 11.9 ± 1.42 N; p =0.83). In femurs, Ca repletion increased (DEF: 176 ± 1; RP: 214 ± 3; p < 0.0001) but did not completely restore (RP: 214 ± 3; PF: 243 ± 8 mg Ca/g; p < 0.0001) femur calcium concentration. However, cortical thickness (measured at midshaft of femur diaphysis) was completely restored by Ca repletion (RP: 0.6; PF: 0.6 mm; p = NS). Findings from this animal model suggest that the deleterious effects of calcium deficiency during adolescence can be reversed with proper dietary Ca intakes.