In the VAT of the Ob + Pre-T2D group, glucagon (1nM) stimulation decreased lactate production (Ob + Pre-T2D: glucagon (0 nM), 45.33 ± 15.61 nmol/mg of VAT vs. glucagon (1 nM), 20.69 ± 6.06 nmol/mg of VAT, Δ −54.36%, p < 0.05), whereas, in a higher concentration (10 nM), it also resulted in a decrease in alanine production (Ob + Pre-T2D: glucagon (0 nM), 0.97 ± 0.40 nmol/mg of VAT vs. glucagon (10 nM), 0.70 ± 0.32 nmol/mg of VAT, Δ −28.04%, p < 0.05). The gene discussed is GCG; the disease is type 2 diabetes mellitus.