{'fraction_non_alphanumeric': 0.04050355774493705, 'fraction_numerical': 0.0180623973727422, 'mean_word_length': 4.573170731707317, 'pattern_counts': {'":': 0, '<': 2, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
[Influence of estradiol on tryptophan hydroxylase and 5-hydroxytryptamine content in raphe nuclei of rats under forced swimming stress].

OBJECTIVE
To investigate the effect of estradiol (E2) on tryptophan hydroxylase (TPH) and 5-hydroxytryptamine (5-HT) content in raphe nuclei of rats under forced swimming stress and explore the role of estrogen and stress in disease mechanism of depression in women.


METHODS
At Week 3 post-ovariectomy, 35 ovariectomized (OVX) female SD rats were randomly divided into 5 groups (n = 7): non-stress group, control group, estradiol (E2) group and fluoxetine (FLX) group and E2 plus FLX group. Animals were administered with different drugs for 2 weeks. At Day 14, animals except those in the non-stress group were subjected to the 15 min forced swimming test (FST). At 2 hours post-FST, all animals including those in the non-stress group were perfused with 4% paraformaldehyde and brains removed for TPH and 5-HT immunofluorescence staining. We compared the content of TPH and 5-HT by observing and calculating the integrated optical density (IOD) of immunofluorescent-positive signals in raphe nuclei.


RESULTS
(1) The IOD value of TPH- and 5-HT-positive region in raphe nuclei of rats in the control group was significantly lower than that of the non-stress group (P < 0.01); (2) the IOD value of TPH- and 5-HT-positive region in raphe nuclei of rats in the E2, FLX and E2 plus FLX groups was significantly higher than that in the control group (P < 0.05).


CONCLUSION
Forced swimming stress can decrease the TPH and 5-HT content in raphe nuclei. Such changes can be prevented by a pre-administration of estradiol. Similar results are observed with antidepressant fluoxetine. These effects may underlie the role of estradiol and stress in the disease mechanism of depression in women.