The effect of environmental on spontaneous activities and expression of c-Fos, 5-HT in the hippocampal neurons of rats with posttraumatic stress disorder

Abstract

Objective To investigate the expressions of c-Fos, 5-HT and spontaneous activities in single prolonged stress(SPS) stress rats , and to study the possible mechanism of posttraumatic stress disorder(PTSD). Methods forty-eight male SD rats were randomly divided into 6 groups: Individual living+ SPS group (IS group), Individual living+ control group (IC group), Enriched environment+ SPS group (ES group), Enriched environment+ control group (EC group), control+ SPS group(CS group), control group(C group), 8 rats in each group, spontaneous activities were measured before the experiment and post experiment at week 1, 2. And the expressions of c-Fos, 5-HT in the hippocampus were examined by immunohistochemical staining. Results (1)Spontaneous activity: there were no differences of crossing number and distance among 6 groups before experiment(P>0.05). On SPS 14 days the crossing number and distance of IS group (12.12±9.64, (2.71±1.99)m) decreased compared with the CS group(45.25±8.37, (6.37±1.18)m, P<0.05), and ES group (69.75±10.05, (10.69±1.50)m) showed significant increase compared with CS group (P <0.05). (2)5-HT: the expression of 5-HT in the hippocampus of IS group(0.1125±0.0095) was significantly higher than that in CS group(0.6138±0.0059, P<0.05), menwhile lower in ES group(0.0495±0.0074, P<0.05). (3)c-Fos: compared with CS group(0.3108±0.0074), the expression of c-Fos in the hippocampus of IS group(0.3585±0.0150, P<0.05) significantly increased, but decreased in ES group(0.2613±0.0063, P<0.05). Conclusion Enriched environmental can improve the level of activities in PTSD rats, and to reduce the the expression of c-Fos and 5-HT in the hippocampal neurons. Key words: Posttraumatic stress disorder; Single prolonged stress; Enriched environment; Individual living; c-Fos; 5-hydroxytryptamine