Anna explored the intricacies of action potential-evoked calcium signals in prefrontal pyramidal cells and found that there is a rather complicated and interesting arrangement of different channel types that give rise to different calcium signals through this ever-so-important neuronal structure. Take a look here:

Functional microstructure of CaV-mediated calcium signaling in the axon initial segment.
Lipkin AM, Cunniff MM, Spratt PWE, Lemke SM, Bender KJ.
bioRxiv. 2020