Objective: To observe the effect of tribulus terrestris saponins (TTS) on behavior and neuroendocrine of chronic mild stress (CMS) depression rats.
Methods: Thirty male Sprague-Dawley rats were randomly allocated to six groups: vehicle group, CMS group, CMS + fluoxetine group and CMS + TTS of low-dosage (0.375 g/kg), medium-dosage (0.75 g/kg) and high-dosage (2.25 g/kg) groups. All rats except the vehicle group singly housed and exposed an unpredicted sequence of mild stressors. The behavior of rats was detected by open-field test (OFT) and sucrose preference test (SPT). The concentration of corticotropin-releasing factor (CRF) and adrenocorticotropic hormone (ACTH) in serum of the rats were detected by radioimmunoassay. The concentration of cortisol (CORT) in serum was detected by enzyme immunoassay.
Results: CMS procedure not only significantly decreased the scores of crossing, rears and grooming in OFT and the sucrose preference in SPT (all P < 0.01), but also markedly increased serum CRH and CORT levels (both P < 0.05). Treatment with TTS (0.75 and 2.25 g/kg) could significantly prevent all of these abnormalities induced by CMS (P < 0.05, P < 0.01).
Conclusion: CMS can affect rat behavior and neuroendocrine and cause depression. TTS has the antagonism on CMS and produce antidepressive effects.