Fig. 1.

Chemogenetic activation of endogenous arginine vasopressin (AVP) suppressed food and water intake with aberrant circadian rhythmicity. A Schematic illustration of a chimeric AVP-hM3Dq-mCherry BAC clone transgene construct. B Fos-immunoreactivity (-ir) (green) in mCherry neurons (red) at 120 min after subcutaneous (s.c.) injection of Saline (1 mL/kg) or clozapine-N-oxide (CNO, 1 mg/mL/kg) in the suprachiasmatic nucleus (SCN), supraoptic nucleus (SON), and paraventricular nucleus (PVN). The digital images were obtained from the rats treated with CNO. Rectangles encompassed by white dotted lines are magnified in each image. The graph indicates the percentage of Fos expression in mCherry neurons. Scale bars, 200 μm. Scale bars in magnified images, 50 μm. Data are presented as mean ± SEM (n = 6, each). **P < 0.01 vs. Saline. Graphs of cumulative food (C) and water intake (D) after s.c. injection of Saline or CNO are represented. Saline or CNO was subcutaneously administered at 30 min before the commencement of the dark cycle, at ZT 11.5. Food (E) and water intake per hour (F) are also represented beneath each graph. Data are presented as mean ± SEM (n = 14, each). *P < 0.05, **P < 0.01 vs. Saline. Locomotor activity (G) and core body temperature (CBT) (H) were measured by intraperitoneally implanted telemetry probe (Nanotag^®). Saline or CNO was subcutaneously administered at 30 min before the commencement of the dark cycle, at ZT 11.5. Averaged activity (per 5 min) (I) and averaged CBT (J) were calculated every 3 h’ division. Data are presented as mean ± SEM (n = 5, each). *P < 0.05, **P < 0.01 vs. Saline