Fig. 3: Characterization of NOPLight response in vivo to pharmacological agonism and antagonism.
From: Development of a genetically encoded sensor for probing endogenous nociceptin opioid peptide release
a Fiber photometry schematic. Cartoon of NOPLight viral injection and fiber implant in the VTA. b Representative image showing DAPI (blue) and NOPLight (green) expression with fiber placement. c Left: Averaged traces of NOPLight fluorescence after systemic (i.p.) injection of vehicle (veh, black; n = 11 mice) or 1, 5, or 10 mg/kg of selective NOPR agonist Ro 64-6198 (RO, green; n = 5, 12, or 16 mice/group, respectively). Right: Mean NOPLight fluorescence 20–25 min after RO injection increases dose-dependently (two-tailed Mann–Whitney test, **p = 0.0012, ****p < 0.0001). Data represented as mean ± SEM. d Left: Averaged traces of NOPLight fluorescence after 10 mg/kg RO (pink), 10 mg/kg selective NOPR antagonist LY2940094 (LY, o.g., blue), or both (purple) (n = 4 mice). Right: Increase in signal 20–25 min after RO is blocked by LY pretreatment (two-tailed Mann–Whitney test, *p = 0.0286, #p = 0.0286, n = 4 mice). Data represented as mean ± SEM. e Same as (d) for NOPR antagonist J-113397 (J11, i.p.) (two-tailed Mann–Whitney test, ##p = 0.0028, ####p < 0.0001, ****p < 0.0001, n = 9 mice, RO; 4 mice, J11; 9 mice, J11 + RO). Data represented as mean ± SEM. f Top: Cartoon of FLEX-NOPLight or NOPLight-ctr viral injection and fiber implant in the VTA. Bottom: Representative image showing expression of DAPI (blue) and FLEX-NOPLight (left, green) or NOPLight-ctr (right, green), with fiber placement in VTA. g Averaged traces of NOPLight (green), FLEX-NOPLight (blue), or NOPLight-ctr (gray) fluorescence (n = 16, 3, 6 mice, respectively) after systemic (i.p.) injection of 10 mg/kg RO. Data represented as mean ± SEM. h Area under the curve (AUC) of each NOPLight variant after RO injection (two-tailed Mann–Whitney test, *p = 0.0275, ***p = 0.0001, ****p < 0.0001, ns not significant (p = 0.9577), #p = 0.0238, ####p < 0.0001. Group sizes left to right: n = 11, 5, 12, 16, 3, and 6 mice). Data represented as mean ± SEM. PN paranigral VTA, veh vehicle, BL baseline.
