Levels of Ca_V1.2 L-Type Ca²⁺ Channels Peak in the First Two Weeks in Rat Hippocampus Whereas Ca_V1.3 Channels Steadily Increase through Development

Figure 5

Intensity of staining with Ca_V1.2 and Ca_V1.3 antibodies in the CA1 region of the hippocampus. No differences in the distribution pattern of the two channels were noted across the ages tested (day 1, 4, 6, 8, 12, 15, 21, and 72; two-way ANOVA followed by pairwise comparison using the Holm-Sidak method) so that the intensity in each layer was pooled across all ages. The intensity for each layer of every section was normalized by dividing by the intensity in the pyramidal cell layer of that specific section. Comparisons were made between the distal radiatum (~100 μm from pyramidal layer), proximal radiatum, and stratum oriens for each antibody with a two-way ANOVA followed by pairwise comparisons using the Holm-Sidak method. The intensity of the labeling with Ca_V1.3 antibodies in the distal radiatum and stratum oriens compared to the proximal radiatum was significantly different (unadjusted 𝑃=0.009 and 𝑃=0.020, resp.). A one sample 𝑡-test was utilized to compare each layer to the pyramidal layer; **Ca_V1.2, 𝑃<0.001(𝑁=48); *Ca_V1.3 𝑃<0.005(𝑁=43).