Effects of Paeoniae Radix Rubra on CRF, c-Fos and TH in the Forced Swimming Test

Abstract

ABSTRACT Objectives : For the purpose of verifying the anti-depressant effect of Paeo niae Radix Rubra(PR), the expression of corticotropin-releasing factor(CRF), c-Fos and tyrosine hydroxylase(TH) was evaluated after performing the Forced Swimming Test(FST). Methods : Spraque-Dawley rats were ingested PR extract(100mg/kg, 400mg/kg, p.o.) for 3 times prior to FST. And the expression of corticotropin-releasing factor(CRF), c-Fos in the paraventricular nucleus(PVN) and tyrosine hydroxylase(TH) in the locus coelureus(LC) and ventral tegmental area(VTA) was measured immunohistochemically after FST. Results : The duration of immobility was significantly decreased in PR 100mg/kg Group and PR 400mg/kg Group, in comparison with the control group (p<0.001). The expr ession of CRF in the PVN was significantly decreased in PR 400mg/kg Group in comparison of the control gro up (p<0.05). The expression of c-Fos in the PVN was rather significantly increased in PR 100mg/kg Group in comparison with the control group, while almost no change was demonstrated in PR 400mg/kg Group. The ex pression of TH was significantly decreased in VTA in comparison with the control group (p<0.05), but the number of expression cells in LC was slightly decreased in case of PR 100mg/kg group while it was increased in case of PR 400mg/kg Group.Conclusion : Judging from the result of the aforementioned tests, Paeoniae Radix Rubra has decreased immobility. In addition, it has also decreased the expression o f CRF and the expression of TH in VTA, while the expression of c-Fos and of TH in LC has no significance. Theref ore, it is believed that Paeoniae Radix Rubra has an anti-depressant effect by decreased immobility through t he reduced expression of CRF and TH in VTA.Key words : Paeoniae Radix Rubra, FST, CRF, c-Fos, TH, anti-depression