Figure 6: Shrm4 silencing in vivo increases anxiety and impaired social behaviours.

(a) Experimental design for investigating behavioural effects of Shrm4 silencing in rat hippocampal CA1. Rats were injected bilaterally with either AAV5-scrambled#1 (or #2) or AAV5-shRNA#1 (or #2) and tested after 3 weeks. (b) No change in motor function in terms of total number of counts evaluated in an automated activity cage for 30 min between Shrm4 knockdown or control animals. (c) A reduced number of open-arm entries and time spent in the open arms for Shrm4 knockdown; no difference in the total number of entries (open-arm entries: Scrambled#1 versus shRNA#1: n=12, 8; *P=0.045; t-test; Scrambled#2 versus shRNA#2: n=5, 5; **P=0.005; t-test) (time spent in the open arms: Scrambled#1 versus shRNA#1: n=8, 8; *P=0.0307; t-test; Scrambled#2 versus shRNA#2: n=8, 8; *P=0.0133; t-test). (d) An increased number of marbles buried and a decreased latency to the first burial were observed in knockdown animals (buried marbles: n=11, 10; **P=0.008; t-test) (latency: n=10, 10; ***P=0.0003; t-test). (e) In the sociability and social novelty test, a reduced time close to stranger 1 in the sociability test and to stranger 2 in the social novelty test was observed in AAV5-shRNA#1 rats compared with AAV5-scrambled#1 rats; (Sociability: n=5, 5; ***P<0.0001; t-test; social novelty: n=5, 5; ***P=0.0002; t-test). All histograms were presented as mean±s.e.m. (f) Tube test—AAV5-shRNA#1 rats showed a greater aggression compared with AAV5-scrambled#1 rats. n=5; **P=0.0041; Fisher’s exact probability test.