CACNA1C and Alzheimer disease: Accordingly, while Cav1.2 association with UB was significantly decreased in AD (AD vs. WT), an increased ubiquitination of Cav1.2 was seen in E2 (AD + E2)‐ or PPT (AD + PPT)‐treated AD mice but not DPN (DPN + AD)‐treated AD mice (Figure 5c–e).