GAD2 and obesity due to melanocortin 4 receptor deficiency: Next, we designed and unilaterally injected AAV-hSyn-DIO-Cacna2d1-pA and AAV-hSyn-DIO-eGFP (1:1) into the right-lateral region of the vlPAG of DIO Gad2-Cre mice to overexpress CACNA2D1 in HFD-induced obesity mice.