Fig 2: Effects of aggression stress on mRNA and protein expression of AVP, AVPR, OT, and OTR in different brain areas of AMYG, MPOA, and PVN of voles. Data are shown as mean ± SE. Asterisks indicate significant differences between groups (* P < 0.05; ** P < 0.01; *** P < 0.001). Control, with no fighting; Fight, with fighting treatment between two voles.

Fig 3: Effects of crowding stress on the mRNA and protein expression of AVP, AVPR, OT, and OTR in brain regions of AMYG, MPOA, and PVN of voles. Data are shown as mean ± SE. Asterisks indicate significant differences between groups (* P < 0.05; ** P < 0.01; *** P < 0.001). 1, low‐crowding group with one neighbor; 3, medium‐crowding group with three neighbors; 8, high‐crowding group with eight neighbors.

Fig 4: The association between population density and mRNA expression of AVP, AVPR, OT and OTR in brain areas of AMYG, MPOA and PVN. The fitted lines are presented with their 95% confidence interval. C, control enclosures; F, food supplementation enclosures; LG, light grazing enclosure; MG, moderate grazing enclosure; LP, light rain supplementation enclosure; MP, moderate rain supplementation enclosure. Data are shown as mean ± SE. Asterisks indicate significant differences between density groups (*P < 0.05; **P < 0.01; ***P < 0.001)

Fig 5: Expression of AVP, V1aR and V1bR mRNA in hypothalamus and trigeminal ganglion. a The mRNA levels of AVP, V1aR and V1bR in HT and, b in TG. Expression was normalized to housekeeping gene GAPDH. Data were obtained by real-time PCR and are expressed as mean ± s.e.m., n = 6, *P < 0.05, **P < 0.01 and ***P < 0.001