The typographical corrections below were made to the article on the date noted. These changes have been incorporated in the article and the details are documented here.

8 September 2005:

In the "Na⁺/K⁺ATPase activity assay" section of Methods, the sentence:

Experiments were repeated a minimum of five times.

was added after:

ATPase activity was measured using a protocol modified from Else and coworkers [47].

In the "Na⁺/K⁺ATPase activity assay" section of Methods, the sentence:

Na⁺/K⁺ATPase activity was calculated as the difference in inorganic phosphate liberated in the presence and absence of ouabain and expressed as μmoles PO₄ released per mg protein per hour.

was clarified with two parentheticals to:

Na⁺/K⁺ATPase activity was calculated as the difference in inorganic phosphate liberated in the presence (Mg²⁺/Ca²⁺ATPase) and absence (total ATPases) of ouabain and expressed as μmoles PO₄ released per mg protein per hour.

and the following sentence was added after it:

Both, Na⁺/K⁺ATPase and Mg²⁺/Ca²⁺ATPase activities were plotted as a function of age.