Cytosolic free calcium in lymphoblasts from young, aged and Alzheimer subjects

Altered cellular calcium homeostasis may be important in the pathophysiology of aging and Alzheimer's disease. Calcium transport by freshly isolated lymphocytes declines with Alzheimer's disease compared with age-matched controls. To determine if these changes occur in the absence of complications due to drugs, diet or any of the other variables that are dependent upon the state of the patients, cytosolic free calcium ([Ca2+]i) was determined in cultured lymphoblasts from young and aged control subjects, as well as from Alzheimer patients. Lymphoblast [Ca2+]i was determined with the fluorescent probe fura-2 in either the presence or absence of serum. In cells that were grown in serum free medium, neither growth rates nor [Ca2+]i varied between groups. Growing cells in serum containing medium doubled growth rates and [Ca2+]i. However, [Ca2+]i from young, aged and Alzheimer groups were still similar. Thus, an age- or Alzheimer-related alteration in [Ca2+]i does not occur in cultured lymphoblasts.