The transgenic construct contains an HS4 insulator-Tet response element/promoter (pTRE2)-loxP-Stop-loxP-CaMP8s-WPRE-pA-HS4 insulator-pCAG-lox2272-Stop-lox2272-FLAG-IRES-tTA2-pA cassette introduced to the Igs7 intergenic region. gCaMP8s (sensitive) incorporates a hexa-histidine affinity tag, an endothelial nitric oxide synthase peptide (ENOSP; modified with N19T, S24I, and S26M), a circularly permutated green fluorescent protein (cpGFP; modified with Q88E), the rat calcium-binding protein calmodulin (CaM; modified with F286Y and Q315H), and LKI amino acid linkers that replace the RS20 (previously referred to as M13) linkers. (J:101977)