Copper (Cu) is required for all basic biochemical and physiological processes. The objective of this study was to compare the effect of two different chemical forms (sulfates and glycinate chelates also below the recommended dose) of Cu administered to adult rats on the biomechanical and morphometric properties of femur. Male rats at the age of 12 weeks were used in the 12-week experiment. The control diet provided the required Cu level from sulfate (S-Cu), and the other diets were supplemented with Cu-glycine complex. The Cu-Gly-treatment, irrespective of its concentration, did not influence the bone mass and length. The Cu-Gly-treatment in 100 and 75% of daily demand increased mechanical endurance. The Cu-Gly-treatment (regardless of its concentration) increased the real bone volume in epiphysis and decreased the total thickness and zone I of the articular cartilage compared to the control group supplemented with S-Cu. The Cu-Gly-treatment enhanced the content of proteoglycans (except the OG50 group). Dietary Cu given to adult rats in the Cu-Gly complex covering the daily demand in 75% exerted a positive effect on bone metabolism and appeared to be the most effective among the investigated doses of the organic form.
Keywords: Adult rat; Bone histomorphometry; Copper; Cu-Gly; Mechanical parameter.