This result, indicating that almost exclusively GABAergic astrocytes and neurons are able to uptake MWCNTs in vivo after their intranasal delivery, corroborate the previously reported in vitro evidence of MWCNT internalization in mouse cortical GABAergic astrocytes.43 Moreover, although the percentage of total GAD+ cells did not vary neither after diabetes induction nor after treatment with both MWCNTs (Fig. 6C), the percentage of GAD+ cells that internalized a-MWCNTs 2 was significantly decreased in treated diabetic rats as compared to treated healthy rats (Fig. 4D). Here, GAD1 is linked to diabetes mellitus.