**4. Voltage-gated Ca2+ channels**

Vascular smooth muscle cells express several subtypes of VGCCs [9]. These channels have been shown to be important for vascular smooth muscle contraction, and some subtypes have been implicated in relaxation mechanisms. In this section, we will focus on the role of two key subtypes of VGCCs, namely, LTCCs and T-type Ca2+ channels (TTCCs), in regulation of vascular smooth muscle excitability.
