GLS and hypothyroidism: In an attempt to define at the molecular level the mechanisms for these changes we measured the expression of relevant enzymes by qPCR: no effects of Mct8 gene inactivation or of hypothyroidism were found on the expression of Gad1 (glutamate decarboxylase), Glud1 (glutamate dehydrogenase), Atp1a3 (Na+K+-ATPase), Gls (glutaminase), Glul (glutamine synthetase), and Gabat (GABA transaminase), nor we found differences in the relative content of both forms of glutamate decarboxylase (GAD65 and GAD67) by western blotting (data not shown).