Effect of Hypericum perforatum on Growth and Brain Monoamine Neurotransmitters in Stressed Rats

This study aimed to investigate the effects of Hypericum perforatum on growth and brain monoamine
neurotransmitters in chronic－stressed rats. Fifteen individuals were divided into three groups including control, stressed
and treated with H. perforatum group. The rats in both stressed and the H. perforatum groups were stressed for 7 days,
and the rats in the latter group were fed with H. perforatum for 10 days after stress. The brain tissues of the rats in all
three groups were collected to analyse the content of homovanillic acid (HVA), norepinephrine (NE), dopamine (DA)
and5-hydroxytryptamine (5-HT) after the experiment was finished. The indexes above were determined by the method of
high pressure liquid chromatogram (HPLC). The results showed that the daily growth mass in the stressed group
significantly decreased compared with the control group, while the ones of H. perforatum group were higher than those of
the stressed group. The HVA levels of the Hippocampus，striatum and prefrontal lobe in the stressed group had no
significant differences compared with the control group, though there was an increase tendency in the stressed group. The
stress had no significant effect on the levels of NE, DA and 5-HT. The DA levels of striatum in the H. perforatum group
were significantly higher than those in the stressed group, while DA levels of prefrontal lobe were significantly decreased
compared with the stressed group. These results suggest that H. perforatum can alleviate the growth decrease caused by
stress, and can partly regulate the levels of monoamine neurotransmitters in the brain of stressed rats.