Age changes in some inorganic constituents of bone and aorta: a comparative study in wild-trapped and laboratory mice...

Age changes in tibia Ca, Mg, Na and K concentrations in wild populations of house mice trapped on the islands of Skokholm and May were compared with the changes monitored in a laboratory-bred strain of Skokholm mice, and in Tuck albino mice. Strain differences were recorded in the temporal changes of Ca, Mg and Na--the wild-trapped Skokholm population having a particularly characteristic alteration in tibial chemistry. Strain differences in bone-electrolytes were attributed predominantly to fundamental genetic differences between populations. Tibia Na and K levels were far more variable than the Ca and Mg levels in all four strains. Electrolyte variability was greater in the wild populations than in laboratory populations. Some thoracic aortas taken from female mice trapped on Skokholm were highly calcified, due possibly to gross arteriosclerosis produced by the endocrine events of reproduction. Elevated calcium levels were not detected in male aortas taken from the wild; neither were the aortas of male and female laboratory-bred Skokholm mice subject to gross calcification.