Fig. 3: Effects of postnatal OXT administration on C-section-associated anxiety phenotype.

A Early postnatal treatment with low-dose OXT decreased the number of marbles buried in the CS group. Mode of delivery effect (F (1, 73) = 4.716, p = 0.033); treatment effect (F (2, 73) = 2.258, p = 0.112); mode of delivery × treatment (F (2,73) = 3.351, p = 0.041) ([VB control n = 12, VB 0.2 OT n = 14, VB 2 OT control n = 13, CS control n = 15, CS 0.2 OXT n = 12, CS 2 OXT n = 13]). B OXT administration did not improve C-section-induced anxiety-like behaviour in the elevated plus maze. Mode of delivery effect (F (1, 74) = 7.614, p = 0.007); treatment effect (F (2, 74) = 0.663, p = 0.518); mode of delivery × treatment (F (2,74) = 0.820, p = 0.444). C There were no significant differences in the number of entrances of the closed arms of the EPM. Mode of delivery effect (F (1, 74) = 0.843, p = 0.361); treatment effect (F (2, 74) = 0.829, p = 0.441); mode of delivery × treatment (F (2,74) = 1.497, p = 0.231). ([VB control n = 12, VB 0.2 OT n = 14, VB 2 OT control n = 13, CS control n = 16, CS 0.2 OXT n = 12, CS 2 OXT n = 13]).C There were no significant effects on time spent in central zone of an aversive-open field. Early postnatal treatment did not reverse C-section-mediated effects on the total distance travelled in an aversive open-field arena. Time in the central zone: Mode of delivery effect (F (1, 65) = 8.167, p = 0.006); treatment effect (F (2, 65) = 2.079, p = 0.133); mode of delivery × treatment (F (2,65) = 7.848, <0.001) ([VB control n = 9 VB 0.2 OT n = 11, VB 2 OT control n = 13, CS control n = 14, CS 0.2 OXT n = 12, CS 2 OXT n = 12]). Total distance travelled: Mode of delivery effect (F (1, 65) = 5.531, p = 0.022); treatment effect (F (2, 65) = 0.713, p = 0.261); mode of delivery × treatment (F (2,65) = 2.164, p = 0.123) ([VB control n = 9 VB 0.2 OT n = 11, VB 2 OT control n = 13, CS control n = 14, CS 0.2 OXT n = 12, CS 2 OXT n = 12]). A–C Two-way ANOVA, followed by LSD post-hoc. Data are represented as Mean ± Standard Error of the Mean (S.E.M.). Male offspring in each group is derived from three independent litters. *p < 0.05, *p < 0.01 and ***p < 0.001. OXT oxytocin, VB vaginal birth, CS C-section.