Immunofluorescence staining and RT-qPCR of CVP neurons isolated from rat hearts found that the Cav1 and Cav2 gene families are expressed in CVP neurons, and T2DM specifically reduces the expression of both the Cav2.2-encoding transcript and protein, resulting in diminished N-type calcium channel function and reduced cell excitability [44]. This evidence concerns the gene CACNA1B and type 2 diabetes mellitus.