Microtransplantation of mammalian neurolemma is a tool to examine the endogenous structure and function of transmitter receptors and ion channels associated with the central nervous system. Microtransplanted neurolemma can originate from a variety of sources, possess ion channels and receptors in their native configuration, and are applicable to examine diseases associated with different channelpathies. In these experiments, we examined the age-related differences in VSSC expression and concentration-dependent responses to pyrethroids in juvenile and adult rat brain tissue microtransplanted in Xenopus oocytes. Automated western blotting results indicate that adult neurolemma exhibited 2.5-fold higher level of expression of VSSCs compared with juvenile neurolemma when normalized to the housekeeping protein β-tubulin. The predominate isoform expressed in both tissues was Na_v1.2 with both showing a significant difference from zero. Adult neurolemma, however, expressed 2.8-fold more Na_v1.2 than juvenile and also express Na_v1.6 at a higher level (2.2-fold). In addition, neurolemma tissue microtransplanted into Xenopus oocytes showed reconstituted native ion currents in the plasma membrane of oocytes that was sensitive to TTX and abolished by choline ion replacement, functionally demonstrating the presence of VSSC. Increasing concentrations of permethrin and deltamethrin exhibited concentration-dependent increases in TTX-sensitive current from both adult and juvenile tissues. Concentration-dependent response curves were analyzed using the equivalence test and the slopes of the curves were different (p < 0.05). VSSCs associated with juvenile neurolemma were up to 2.5X more sensitive to deltamethrin than VSSCs in adult neurolemma. In contrast, VSSCs from juvenile neurolemma were less sensitive than adult VSSSs at lower concentrations (0.6-0.8X) and more sensitive at higher concentrations (up to 2.4X). However, because the expected brain concentrations in humans following realistic exposure levels are approximately 21- (deltamethrin) to 333- (permethrin) times below the threshold for response in rat neurolemma, age-related differences, if any, are not likely to be toxicologically relevant.