AIMThe expression of VEGF in rat ovaries corpus luteum and its expression pattern were observed to investigate the effect of VEGF on luteal formation and regression.

METHODSThe model of immature rat of pseudopregnant was established using pregnant mare's serum gonadotropin (PMSG) and human chorionic gonadotropin (hCG), the expression of VEGF in corpus luteum was detected by immunohistochemistry, the levels of VEGF in corpus luteum was measured by ELISA, and the levels of NO in corpus luteum was measured by chemistry assay.

RESULTSVEGF expressed weakly in rat corpus luteum on the day 1, and enhanced gradually from day 3 to day 5, then went up to the peak on the day 7, and maintained to day 9. On the day 11, the expression of VEGF began to decrease. The levels of VEGF were similar to the expression of VEGF. The levels of NO appeared like double wave. The levels increased gradually from day 1 to day 5, and peaked on the day 7, then decreased on the day 9, while lightly increased on the day 11, and showed significant increase and reached the highest on the day 13, then decreased the lowest on the day 15.

CONCLUSIONThere is a intimate temporal relationship between the expression of VEGF and angiogenesis in corpus luteum, VEGF may play a role in luteum formation by improving angiogenesis mediated by NO, NO may play a role in luteum regression as a luteolytic during the late luteal phase.

Animals ; Corpus Luteum ; metabolism ; Female ; Nitric Oxide ; metabolism ; Pseudopregnancy ; metabolism ; Rats ; Rats, Sprague-Dawley ; Vascular Endothelial Growth Factor A ; metabolism

To examine the electrophysiological properties of luteal cells and the relationship between membrane potential and luteal steroidogenic capacity, the membrane potential of luteal cells and the luteal steroidogenesis were measured under different ionic conditions following treatment with various drugs and gonadotropins. The membrane potential of luteal cells did not vary throughout the estrous cycle and was -55 +/- 1 mV. The membrane potential was highly dependent upon the external K+ concentration and was depolarized by the deprivation of external Ca2+, however) there seemed to be a lower K+ permeability in luteal membranes as the presence of 10-9 M valinomycin, a K+ ionophore Caused hyperpolarization from -55 to -91 mV. Luteal progestin production was increased in a high K+ solution but not m a Ca2+-free solution indicating that Ca2+ may be essential for steroid synthesis and/or secretion by luteal cells. Gonadotropins and ouabain induced a depolarization of the membrane potential and stimulated luteal steroidogenesis; however; prostaglandin F2alpha stimulated only steroidogenesis without any changes in membrane potential. These results suggest that the relationship between steroidogenesis and the changes in membrane potential by drugs and gonadotropins is still obscure and remains to be eluridated. The relationship between membrane potential and steroidogenesis in the luteal cell may be dependent upon the availability of intracelluar Ca2+.
Animal ; Corpus Luteum/*metabolism ; Estrus/metabolism ; Female ; Ions ; Luteal Cells/*metabolism ; Membrane Potentials ; Rats ; Rats, Inbred Strains ; Steroids/*biosynthesis ; Support, Non-U.S. Gov't

OBJECTIVETo investigate the expression changes and regulation of pituitary adenylate cyclase-activating polypeptide (PACAP) mRNA in corpus luteum during pregnancy.

METHODSPregnant 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.

RESULTSWith 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.

CONCLUSIONPACAP, 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.

Animals ; Cells, Cultured ; Corpus Luteum ; metabolism ; Female ; Pituitary Adenylate Cyclase-Activating Polypeptide ; genetics ; metabolism ; Platelet Activating Factor ; metabolism ; Pregnancy ; RNA, Messenger ; genetics ; Rats ; Rats, Sprague-Dawley

The protein expression of cystic fibrosis transmembrane conductance regulator (CFTR), a cAMP-activated Cl(-) channel, in ovarian stimulated premature female rat ovary during a cycle of follicle development and corpus luteum formation was investigated. Animals were injected with 10 U pregnant Mare's serum gonadotropin (PMSG) and subsequently 10 U hCG 48 h later. Time-dependent immunohistochemistry and Western blotting experiments were performed before and 24, 48, 72 h after hCG treatment. The immunohistochemistry revealed that administration of PMSG stimulated the CFTR expression in thecal cell layer and granulosa cell layer of mature follicles 48 h post injection, coincident with the PMSG-induced peak in follicular estradiol. However, the expression of CFTR in the granulose lutein cell layer and thecal lutein cell layer was time-dependently reduced following hCG injection, in accordance with the gradually increased progestogen level during luteum corpus formation. Western blotting analysis demonstrated that rat ovarian tissue expressed the special CFTR band at 170 kD. It is concluded that cAMP-dependent Cl(-) channels are involved in regulation of follicle development and luteum formation.
Connective Tissue Growth Factor/genetics ; Connective Tissue Growth Factor/*metabolism ; Connective Tissue Growth Factor/*physiology ; Corpus Luteum/growth & development ; Ovarian Follicle/growth & development ; Ovary/*metabolism ; Rats, Wistar

The present study aimed to investigate the role of platelet-activating factor (PAF) in progesterone synthesis and vascular endothelial growth factor (VEGF) expression in rat luteal cells. Immature (25-28 days old) female Sprague-Dawley rats were injected subcutaneously with 50 IU pregnant mare serum gonadotrophin (PMSG), and 25 IU 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 incubated without or with different doses (0.1 μg/mL, 1 μg/mL, 10 μg/mL) of PAF at 37 °C (5% CO(2)) for 24 h, and then progesterone concentration was evaluated by radioimmunoassay (RIA); apoptotic rate and VEGF mRNA expression in luteal cells were assessed by flow cytometry and RT-PCR, respectively. The results showed that PAF promoted progesterone production, with a maximal effect at 1 μg/mL (P<0.05); PAF increased apoptotic rate but not in a dose-dependent manner, and 10 μg/mL PAF enhanced apoptotic rate significantly (P<0.05); furthermore, PAF stimulated VEGF mRNA expression in luteal cells, especially at 1 μg/mL (P<0.01). It is suggested that PAF regulates progesterone synthesis and VEGF mRNA expression in luteal cells to mediate corpus luteum formation in rat ovary.
Animals ; Chorionic Gonadotropin ; pharmacology ; Corpus Luteum ; drug effects ; Female ; Luteal Cells ; drug effects ; metabolism ; Platelet Activating Factor ; pharmacology ; Pregnancy ; Progesterone ; biosynthesis ; Rats ; Rats, Sprague-Dawley ; Vascular Endothelial Growth Factor A ; metabolism

INTRODUCTIONThe aim of this study was to determine the effect of a high-fat diet (HFD) on oocyte maturation and quality in a mouse model.

METHODSFemale BALB/c mice were allocated to one of the following groups: (a) control group (n = 40), which received a controlled diet; or (b) HFD group (n = 40), which received an HFD for 12 weeks. Sections of the ovary were examined histologically. The number of follicles and corpora lutea were counted. In vitro maturation and in vitro fertilisation (IVF) were assessed in germinal vesicle (GV) and metaphase II (MII) oocytes, respectively. The expression of bone morphogenetic protein 15 (BMP15) and leptin receptor genes in GV and MII oocytes was evaluated using reverse transcription real-time polymerase chain reactions.

RESULTSIn the HFD group, there was a decreased number of primordial and Graafian follicles, as well as corpora lutea (p < 0.05). The rate of oocyte development to the MII stage was also reduced (p < 0.001). Cumulus expansion was observed more frequently in the control group than the HFD group (p < 0.05). The IVF rate in the HFD group was lower than that in the control group (p < 0.05). In the HFD group, BMP15 and leptin receptor genes were upregulated in the GV stage (p > 0.05) and MII stage (p < 0.05), compared to the control group.

CONCLUSIONAn HFD reduces folliculogenesis in the primordial and Graafian stages, in vitro maturation and in vitro fertilisation rates, as well as oocyte quality in mice.

Animals ; Body Weight ; Bone Morphogenetic Protein 15 ; metabolism ; Corpus Luteum ; pathology ; Diet, High-Fat ; Female ; Fertility ; Fertilization in Vitro ; methods ; Gene Expression Regulation ; Metaphase ; Mice ; Mice, Inbred BALB C ; Obesity ; complications ; Oocytes ; cytology ; pathology ; Ovarian Follicle ; pathology ; Ovary ; metabolism ; pathology ; Photography ; Polymerase Chain Reaction ; Receptors, Leptin ; metabolism

OBJECTIVE: To explore the effect of compound malt pills (CMP) on polycystic ovarian syndrome (PCOS) rat model induced by letrozole and the underlying mechanisms.
 METHODS: To establish a PCOS rat model, 48 female SD rats aged 6 weeks were randomly divided into 6 groups (n=8): A normal group, a model control group, a positive control group, a low-dose CMP group, a middle-dose CMP group, and a high-dose CMP group. Rats were treated for 21 days after the PCOS model was successfully established. Ovarian morphology changes were observed, and the expressions of ERα and ERβ was examined by immunohistochemistry, Western blot and RT-PCR, respectively.
 RESULTS: Compared with the normal group, the number of follicular cystic dilatation in the model control group was increased and the granulosa cells were decreased. After the treatment, the number of follicular cystic dilatation was reduced compared with the model control group, but the primordial follicles, corpus luteum and granulosa cells were increased. The expressions of ERα and ERβ in the model control group were significantly decreased (P<0.01), which were increased in the intervention groups (P<0.05 or P<0.01).
 CONCLUSION CMP may play a role in the treatment of PCOS by regulating the expressions of ERα and ERβ.
Animals ; Corpus Luteum ; drug effects ; Disease Models, Animal ; Drugs, Chinese Herbal ; pharmacology ; Estrogen Receptor alpha ; metabolism ; Estrogen Receptor beta ; metabolism ; Female ; Granulosa Cells ; drug effects ; Letrozole ; Nitriles ; adverse effects ; Ovarian Follicle ; drug effects ; Polycystic Ovary Syndrome ; chemically induced ; metabolism ; Rats ; Rats, Sprague-Dawley ; Triazoles ; adverse effects