Fig. 4

Intraperitoneal administration of rh-relaxin-2 improved short-term neurological function at 3 days after GMH. Negative geotaxis (a, b) and righting reflex (c) demonstrated that medium (60 μg/kg) and high (90 μg/kg) dosages of rh-relaxin-2 significantly improved neurological function compared to vehicle-treated pups in the first 3 days. *P < 0.05 vs Sham, #P < 0.05 vs GMH + vehicle, $P < 0.05 vs low dosage (30 μg/kg) of rh-relaxin-2, one-way ANOVA, Tukey’s test, n = 7/group. rh-relaxin-2 (60 μg/kg) treatment significantly increased the falling speed and falling latency in both 5 rpm - and 10 rpm (d, e) acceleration groups. In the foot fault test, animals in the vehicle group had significantly more total foot slips compared to the rh-relaxin-2 (60 μg/kg) treatment group (f). The water maze test showed that animals from the vehicle group swam significantly longer in 1 min (g), took more time to find the platform (h), and spent less time in the target quadrant during the probe trial (j, k) compared to the sham animals. In contrast, rh-relaxin-2-treated animals performed better (j, k) than vehicle. *P < 0.05 vs Sham, #P < 0.05 vs GMH + vehicle, one-way ANOVA, Tukey’s test, n = 10/group. In addition, rh-relaxin-2 administration reduced ventricular volume (l, m) and gray matter loss (n), and increased relative cortical thickness (o) and relative white matter area (p) significantly. *P < 0.05 vs Sham, #P < 0.05 vs GMH + vehicle, one-way ANOVA, Tukey’s test, n = 6