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Biomedical subjects

Zhan-Zhuang Tian

Publications and source records attributed to Zhan-Zhuang Tian.

5 recordsLinked to original sources

Electroacupuncture stimulates hypothalamic aromatization.

We have previously reported that the repeated electroacupuncture (EA) stimulation significantly increased the concentrations of circulating estradiol and restored the depressed function of the hypothalamus-pituitary-ovary axis (HPOA) in ovariectomized (OVX) rats. We hypothesize that extragonadal aromatization in specific brain areas might be responsible for these changes. Thus, various assays, including radiometric assay, Western blot, and reverse transcriptase polymerase chain reaction (RT-PCR), were employed to determine the aromatization in the hypothalamus of rats that received both OVX and electroacupuncture (OVX + EA). The results showed that EA significantly increased the aromatase activity as well as the expressions of its mRNA and protein (P < 0.05) in the OVX rats. These results suggest that EA enhances brain aromatization, which might contribute to influence the function of gonadotropin-releasing hormone (GnRH) neurons and promote the hypofunction of the HPOA in the ovariectomized rats.

Animals↗

Decreased hypothalamic aromatization in female rats of true precocious puberty.

The true precocious puberty animal model induced by the single dose of danazol was used for investigating the expressions of hypothalamic aromatase in the advanced onset of puberty in rats. The day of vaginal opening and first estrus showed significant advancement in the model rats compared with the normal and vehicle rats (P < 0.01, respectively). The hypothalamic gonadotropin-releasing hormone (GnRH) mRNA expression increased significantly in the model rats compared with that in the normal and vehicle ones (P < 0.01). The levels of aromatase mRNA and protein expressions detected by RT-PCR and Western blot both decreased in the model rats compared with those in the normal and vehicle groups (P < 0.05). The results suggested that the hypothalamic aromatization might diminish in the onset of true precocious puberty of female rats.

Animals↗

Increased corticortropin-releasing hormone release in ovariectomized rats' paraventricular nucleus: effects of electroacupuncture.

Utilizing push-pull perfusion, we examined secretary profiles of corticotropin-releasing hormone (CRH) in the nucleus paraventricularis (PVN) of freely moving intact (INT) and ovariectomized (OVX) rats, and in the meanwhile the effects of electroacupuncture (EA) on the release patterns of CRH were observed. The PVN was perfused with artificial cerebrospinal fluid between 08:00 and 12:00 h, and perfusates were collected every 10 min. The average CRH output was significantly larger in OVX rats than that in INT and INT with EA (INT+EA) groups. Interestingly enough, the CRH output showed a significant elevation in OVX with EA (OVX+EA) group during the EA procedure and further increase immediately after the EA. It is the first time to present the temporal profiles of CRH secretion in the PVN of OVX and OVX+EA rats.

Analysis of Variance↗

An important role of corticotropin-releasing hormone in electroacupuncture normalizing the subnormal function of hypothalamus-pituitary-ovary axis in ovariectomized rats.

In the present study, the effects of electroacupuncture (EA) at a group of specific acupoints on corticotropin-releasing hormone (CRH) and gonadotropin-releasing hormone (GnRH) immunoreactivity (ir) in the hypothalamuses of ovariectomized rats were observed. Meanwhile the blood E2 level was detected. The results showed that EA might significantly increase the blood level of E2 and GnRH cell number in the ovariectomized rats. The number of CRH neurons was higher in the group ovariectomized with EA than that in the ovariectomized and intact groups. Interestingly enough, only in the group ovariectomized with EA was observed the co-localization of CRH-ir and GnRH-ir substances in one cell of hypothalamic nucleus paraventricularis by immunofluorescent double-labeling histochemistry combining laser con-focal scanning microscope. The results suggest that CRH might be an important factor in EA normalizing the subnormal function of hypothalamus-pituitary-ovary axis.

Animals↗