Cytosolic calcium is normally distributed in brain synaptosomes of normal and chronic renal failure rats

Available data indicate that the basal levels of cytosolic calcium ([Ca2+]i) varies widely in polymorphonuclear leukocytes and in thymocytes. The present study examined whether a similar phenomenon exists in other cells. We measured the basal level of [Ca2+]i in brain synaptosomes of normal and chronic renal failure (CRF) rats. We find these levels (278-439 mM) vary widely in both normal rats and in CRF animals (350-495 mM) as well. However, despite these wide variations, the values followed normal distribution in both groups of animals. The data are consistent with the proposition that the values of [Ca2+]i in many cells display wide variations among a particular species and the levels are most likely predetermined genetically for each animal.