Effects of ginsenoside Rb1 and Rg1 on synaptosomal free calcium level, ATPase and calmodulin in rat hippocampus.

Calcium homeostasis in synaptosomes is altered during aging. The intrasynaptomal free calcium concentration ([Ca2+]i) was determined in 3- and 24-month-old rats treated with or without Rb1 and Rg1. As expected, the [Ca2+]i level increased with age. Treatment with Rbl and Rgl elicited an obvious decrease of [Ca2+]i content, especially in aged rates. In addition, Rb1 and Rgl significantly stimulated the activity of Na+, K+-ATPase while Rbl inhibited the activity of Ca2+, Mg2+-ATPase and calmodulin. In view of the close relationship of [Ca2+]i level with aging, the changes of [Ca2+]i induced by Rbl and Rgl, as shown by our results, might provide an explanation of the mechanisms of their antiaging function.