Wu Y.-Y.,Zhefiang Chinese Medical University |
Jiang Y.-L.,Zhefiang Chinese Medical University |
Shao X.-M.,Zhefiang Chinese Medical University |
Zhao X.-Y.,Zhefiang Chinese Medical University |
And 2 more authors.
Acta Anatomica Sinica | Year: 2015
Objective: To observe the distribution of 5-hydroxytryptamine (5-HT) in the dorsal raphe nucleus (DRN) of the rat with pain-depression dyad. Methods: Twenty male SD rats were randomly divided into normal group and model group (n = 10). The model group had pain-depression dyad induced by subcutaneously injecting reserpine daily for three consecutive days. The behavior was tested by mechanical pain thresholds and the depressive emotion was examined by open-field test and elevated-zero-maze test. The expressions of 5-HT in DRN (bregma-6.8, -7.3, -7.8 mm) were detected with immunofluorescence test. Results: Compared with the normal group, rats in the model group showed a declined pain threshold of the left hind leg and depressive-like behavior. The 5-HT labeled cells at different levels of DRN (bregma-6.8,-7.3,-7.8mm) of normal rats were 106.00 ± 10.21, 96.67 ± 24.50 and 195.67 ± 2.33, while the model group rats were 61.67 ± 14.53, 72.33 ±34.35 and 53.67 ±26.77. In comparison with the normal group, the expressions of 5-HT in DRN (bregma-7.8mm) decreased significantly in the model group (P < 0.05), but no changes were observed at the levels of bregma-6.8 and-7.3mm (P > 0.05). Conclusions The pain-depression dyad induced by reserpine injection can cause the declination of 5-HT expressions in DRN. The declination may be related with the expressions of 5-HT in DRN (bregma-7.8mm), but not with the levels of bregma-6.8 and-7.3mm.