Effects of Intracerebroventricular Micro-injection of Kaempferol on Anxiety: Possible GABAergic Mechanism Involved

Kaempferol (KM) is one of the most important plants with neuroprotection and analgesic effects. In addition, bicuculline (BIC) is a competitive antagonist of the GABAA ionotropic receptor (the most important targets of benzodiazepines and other anxiety suppressants). In this study, intracerebroventricular microinjection of KM on anxiety and its interaction with GABAergic mechanism were investigated in male rats.

In this exploratory investigation, the male rats were divided into the following groups: control (saline), groups treated by KM (0.5 and 2 mg/rat), DMSO (1mg/rat), KM 0.5+BIC1 mg/rat, KM 0.5+BIC4 mg/rat, KM 2+BIC1 mg/rat, BIC groups (1, 4 mg/rat), and KM 2+BIC 4 mg/rat. Besides, an elevated plus-maze paradigm was used for the evaluation of the anxiety.

Statistical analysis revealed that the indices of TTOA in KM groups (0.5 and 2 mg/rat) significantly increased in comparison to the control group (P<0.05 and P<0.01, respectively). Moreover, regarding the involvement of the GABAergic system in the anxiolytic-like activity of KM, it was demonstrated that the TTOA related to co-administration of KM (0.5mg/rat) with bicuculline (1mg/rat) significantly reduced, compared to the control group (P<0.05).

According to the obtained results, the use of KM can likely improve anxiety through GABAergic mechanism(s).