From Acupuncture to Interaction between 𝜹-Opioid Receptors and Na⁺ Channels: A Potential Pathway to Inhibit Epileptic Hyperexcitability

Table 2

Voltage-gated sodium channels.

Subunit	𝛼	𝛽
Subtypes	Nav1.1–Nav1.9	𝛽1–𝛽4
Location	Prevalent in the CNS:	Two 𝛽 subunits associated with an α subunit
	Nav1.1, Nav1.2, Nav1.3, and Nav1.6
	Abundant in muscle:
	Nav1.4, Nav1.5
	Primarily in peripheral nervous system:
	Nav1.7, Nav1.8,  and Nav1.9
Cellular distribution	Primary localized in cell body:	Expressed in a complementary fashion (either 𝛽1 or 𝛽3, and 𝛽2 or 𝛽4) with 𝛼 subunit
	Nav1.1 and Nav1.3
	High expression in unmyelinated or pre myelinated axons and; dendrites:
	Nav1.2
	Nodes of Ranvier and axon initial segments as well as in the; somata and dendrites of many projection neurons:
	Nav1.6
Function	Forms the ion-conducting pore and activation and inactivation gates	Modify the kinetics and voltage dependence of gating; Serve as cell adhesion molecules for integrating the channels into the appropriate subcellular domains