SYP and Alzheimer disease: There was a significant decrease in synaptophysin density in the saline-treated 3xTg-AD mice only (F(3,72)=5.7; p < 0.01); Ryanodex-treated 3xTg-AD mice demonstrated normal synaptophysin levels compared to NonTg controls (p > 0.05) where Ryanodex had no effect.