Scn8a-flox Mouse

Scn8a, encoding the voltage-gated Na+ channel Nav1.6, is a crucial gene in the central nervous system. Nav1.6 channels play a key role in the generation and propagation of action potentials in neurons, thus being essential for normal neural function [1,2,3].

Mouse models have been instrumental in understanding Scn8a's function. For example, conditional R1872W mutation mouse models (activated by CRE recombinase) were used to study the effects of Scn8a mutations on different neuron classes and at different post-natal developmental stages. These models showed that certain missense mutations in Scn8a can lead to neuronal hyperexcitability, which is associated with epileptic encephalopathy [1]. Additionally, Scn8a null mutations in mice (like Scn8a(med) and Scn8a(medTg)) are lethal, while incomplete mutations (Scn8a(medJ) and Scn8a(medJo)) and knockout only in cerebellar Purkinje cells allow survival to adulthood. In these mutant mice, resurgent sodium current in Purkinje cells is reduced, leading to decreased spontaneous activity, along with up-regulation of GABA(A) receptors in related regions [4].

In conclusion, Scn8a is vital for normal neural function through its role in sodium channel activity. Mouse models, especially those with gene knockout or conditional knockout, have significantly contributed to understanding its role in epileptic encephalopathy and other neurological disorders. The findings from these models provide a basis for developing new therapies for Scn8a-related disorders [1,3,4].