[Effects and mechanisms of zuogulyin on the ovarian NO production in peri-menopausal rats].

OBJECTIVE: To study the effects and mechanisms of Zuoguiyin (ZGY) on the ovarian nitric oxide (NO) production in peri-menopausal rats. METHODS: The peri-menopausal model rats were respectively administered with low (13.78 g/kg), middle (20.67 g/kg), and high (31.00 g/kg) dose ZGY, and nilestriol for 8 weeks. Normal saline was given by gastrogavage to rats in the model group and the young control group (as the control group). The ovarian NO content and the activity of total nitric oxide synthase (NOS) were detected using nitrate reductase method and chemical colorimetry respectively. The mRNA and protein expressions of inducible NOS (iNOS), endothelial NOS (eNOS), and neuronal NOS (nNOS) were detected using RT-PCR and immunohistochemical assay. RESULTS: (1) Compared with that in the control group, the ovarian NO content and the activity of total NOS in peri-menopausal rats were significantly lower (P < 0.01). Middle and high dose ZGY could obviously up-regulate them (P < 0.01, P < 0.05). (2) The three kinds of NOS expression levels in perimenopausal rats were obviously lower when compared with those of the control group (P < 0.01). Middle dose ZGY could significantly promote all the three kinds of NOS expression levels of pre-senile rats (P < 0.01). High dose ZGY could up-regulate the expressions of iNOS and eNOS, while low dose ZGY could only enhance the iNOS expression (P < 0.01). CONCLUSIONS: The down-regulated expressions of eNOS, iNOS, and nNOS in local ovaries resulted in decreased NOS activity and NO production, which were closely correlated with damaged microcirculatory vascular functions of ovaries in peri-menopausal rats. ZGY could protect rats' ovarian microcirculation by up-regulating the expressions of eNOS, iNOS, and nNOS, and enhancing the ovarian NOS activity and NO production.

Pituitary adenylate cyclase-activating polypeptide mRNA expression in rat testis and epididymis during postnatal development and experimental cryptorchidism.

In the present study, the expression of pituitary adenylate cyclase-activating polypeptide (PACAP) mRNA was investigated in rat testis and epididymis during postnatal development and experimental cryptorchidism using reverse transcription-polymerase chain reaction (RT-PCR) and in situ hybridization. The results revealed that i) in the testis, PACAP mRNA expression was first detected on day 20 after birth and gradually increased from day 20 to reach a maximum level on day 60, mainly in the spermatocytes and round spermatids; ii) in the epididymis, PACAP mRNA was first detected on day 10 after birth and remained at higher levels from day 40; iii) the levels of PACAP mRNA in the testis and epididymis markedly decreased in a time-dependent manner from 1 week after cryptorchid surgery until they had almost disappeared at 4 weeks. These results suggested that the pattern of PACAP mRNA expression is developmentally dependent in both the testis and epididymis, and the expression of PACAP mRNA is regulated by the local temperature within the testis. In conclusion, the pattern of expression of PACAP in the testis and epididymis suggests a possible role of PACAP in spermatogenesis and sperm maturation.

[Expression and regulation of pituitary adenylate cyclase-activating polypeptide mRNA in pregnant rat corpus luteum].

OBJECTIVE: To investigate the expression changes and regulation of pituitary adenylate cyclase-activating polypeptide (PACAP) mRNA in corpus luteum during pregnancy. METHODS: Pregnant rats' ovaries were collected at different time points. The techniques of RT-PCR and in situ hybridization were used to observe expression changes of PACAP mRNA in rat ovaries during pregnancy. To further explore the regulation mechanism of PACAP mRNA expression in corpus luteum, luteal cells were cultured in vitro. Immature (25 - 28 days old) female Sprague-Dawley rats were injected subcutaneously with 50IU pregnant mare serum gonadotrophin (PMSG), and 25IU human chorionic gonadotrophin (hCG) 48 h later, to induce follicular development and luteum formation. On day 6 after hCG administration (the day of hCG administration was the first day), the rats were killed by guillotine and the ovarian luteal cells were collected. After incubation for 24 h, luteal cells were administration with various factors for 24 h. And then expression changes of PACAP mRNA in luteal cells after administration with different factors were detected by RT-PCR, and radioimmunoassay was used to analyze progesterone levels. RESULTS: With the development of pregnancy, the expression of PACAP mRNA increased gradually, reached the peak at pregnancy 19 d, and then decreased. Compared with control group, platelet activating factor (PAF), forskolin and PMA could obviously stimulate PACAP mRNA expression in luteal cells which were cultured with corresponding factors for 24 h. At the same time, progesterone levels in culture media were also elevated. CONCLUSION: PACAP, acting as a local ovary regulator, was closely related to the maintenance of medium-term and late pregnancy. PAF could directly stimulate PACAP mRNA expression in luteal cells, and protein kinase C (PKC) and protein kinase A (PKA) signal pathways could both participate in this process.