OBJECTIVETo explore the influences of orthodontic tooth movement on estrous cycle and estrogen in female rats.

METHODSTwo hundred female rats were divided into control group, one-time activation group, four-time activation group and sham-operated group. Each group was divided again into 4 sub-groups according to the different stage of the estrous cycle. The force-loading groups received repeated intermittent force. Serum estrogen was measured and the change of estrous cycle was recorded.

RESULTSThere were significant variations in the estrogen level among the groups which received mechanical force during the same stage of the estrous cycle (P < 0.01) and among the subgroups within each group (P < 0.05). These experimental treatments affected the estrous cycle of the rats in the groups received force in metestrus and diestrus.

CONCLUSIONSEstrus of rats was the appropriate time for the orthodontic force.

Animals ; Estrogens ; blood ; Estrous Cycle ; physiology ; Female ; Rats ; Rats, Wistar ; Tooth Movement Techniques

The objectives of the present study were to compare the in vitro maturation (IVM), fertilization and early embryonic development of bovine oocytes recovered from ovaries during the follicular, metestrus and diestrus stages of the estrous cycle and at anestrus and pregnancy after maturation in a serum free culture medium. Cumulus oocyte complexes (COCs) collected from ovaries at different reproductive statuses were matured in medium 199 supplemented with 10 g/ml FSH, 10 g/ml LH, 1.5 g/m estradiol, 75 g/ml streptomycin, 100 IU/ml penicillin and 10 mM HEPES. COCs were incubated in 200 microliter droplets of maturation medium 199 under oil for 24 h at 39degrees c and 5% CO2. Matured oocytes were exposed to frozen-thawed TALP swim up, heparin capacitated sperm from two bulls separately in each replicate (20 h, 39C, 5% CO2). After fertilization, the presumptive zygotes were cultured in medium 199 containing 8 mg/ml BSA-V, 100 IU/ml penicillin-G, 75 g/ml streptomycin and 10 mM HEPES for 144 h at 39C and 5% CO2 without medium freshening or change. Oocytes/embryos were fixed, stained with DAPI and evaluated under fluorescent microscope. The IVM rates were almost similar among oocytes from all reproductive statuses (range: 89.8 to 95.4%). However, IVM rates for oocytes from the metestrus (90.6%) and pregnant (89.9%) phases were lower than the other groups. The fertilization rates were lower (p<0.05) for oocytes from the diestrus phase (72.4%) than from the other phases (range: 81.1 to 86.6%). Oocytes, recovered during the metestrus phase of the estrous cycle, resulted in the highest cleavage rate (60.0%), while oocytes from the diestrus phase had the poorest embryonic development (39.8%: p<0.05). Majority of the embryos from all reproductive phases showed a developmental arrest around 8-cell stage. Although the developmental competence of oocytes from pregnant and anestrus animals was lower than that from the other reproductive stages, they could be potentially used as oocyte donors. Long term, in vitro embryo culture without medium freshening or change was hypothesized to have caused the failure to overcome the 8-cell block to development.
Animals ; Cattle/*embryology/*physiology ; Ectogenesis/physiology ; Embryonic and Fetal Development ; Estrous Cycle/*physiology ; Female ; Fertilization in Vitro ; Male ; Oocytes/*growth&development/*physiology ; Pregnancy

In the present study, whether the ADAM-8, -9, -10, -12, -15, -17, and ADAMTS-1 proteins might play a role in mouse uterus during periimplantation period was investigated. Immunoblotting analyses demonstrated that all ADAM proteins consistently appeared throughout days 1 to 8 of pregnancy but with a variation depending on the species of ADAM gene, the progression of pregnancy, and the site of the uterus. Immunohistochemical analyses indicated that ADAM proteins were localized in the luminal or glandular epithelial layers with a varying intensity depending on the species of ADAM and the progression of pregnancy. Particularly ADAM-8, -12, and -15, were predominantly located in the implantation site of the uterine tissues, whereas little or no protein was localized in the interimplantation site. Based upon these observations, it is suggested that the ADAMs might play an important role in the remodeling of the mouse uterus during the periimplantation period.
Uterus/*metabolism ; Time Factors ; Pregnancy ; Mice, Inbred ICR ; Mice ; Immunohistochemistry ; Immunoblotting ; *Gene Expression Regulation ; Female ; *Estrous Cycle ; Embryonic Development ; *Embryo Implantation ; Animals ; ADAM Proteins/*biosynthesis/*physiology

The objective of this study was to determine the effects of superovulation (SOV) on serum and uterine biochemical parameters, uterine bacteriology and cytology and number of transferable embryos (TE). Dairy cows were placed on a Presynch/CIDR Synch protocol. The SOV group was superovulated, induced in estrus, and inseminated, whereas the control group was induced in estrus and inseminated without SOV. Uterine bacteriology and cytology and uterine and serum biochemical parameters were measured at day 7 of the estrous cycle to start the SOV protocol, as well as on the day of embryo recovery (DER). The SOV group produced 7.5 +/- 6.7 oocytes/embryos, of which 3.4 +/- 4.7 were TE. Serum urea and E2 and uterine Glu, CK, LDH, TP, P4 and PGFM in the control group and serum P4 and PGFM and uterine LDH and PGFM in the SOV group were significantly higher (p < 0.01) at DER than day 7. At DER, uterine urea, LDH, PGFM and TP and serum urea, LDH, PGFM, and P4 concentrations were higher (p < 0.01) in the SOV group than the control. There was no significant variation in uterine bacteriology or cytology. Overall, these results infer that SOV affects both serum profile and uterine secretions, and that these changes may influence the number of TE.
Animals ; Blood Chemical Analysis/veterinary ; Cattle/blood/*embryology/*physiology ; Embryo Transfer/veterinary ; *Embryonic Development ; *Estrous Cycle ; Female ; Superovulation ; Uterus/*chemistry/cytology/*microbiology

The circadian clock has been linked to female reproductive physiology and endocrine in mammals. Epidemiological studies of female shift workers have shown increased rates of abnormal reproduction and adverse pregnancy. But little is known how the circadian rhythms affect reproduction. The aim of the present study was to investigate the influences of circadian rhythms on estrous cycle in female mice using clock gene Rev-erb-α knock out (Rev-erb-α(-/-)) mice. To test the fertility of Rev-erb-α(-/-) mice, litter sizes were counted after mating with C57BL/6J male mice. HE staining was used to observe the change of follicle development. The number of embryos of Rev-erb-α(+/+) and Rev-erb-α(-/-) female mice was compared 1.5 d after mating with C57BL/6J male mice. Then Rev-erb-α(+/+) and Rev-erb-α(-/-) female mice were housed to adult, and daily vaginal lavage with 0.9% saline was used to monitor estrous cycle for at least 30 days. Quantity of various cells was counted on specified smears views after staining. We observed estrous cycles of Rev-erb-α(+/+) and Rev-erb-α(-/-) female mice using line plots and periodic spectrograms. The results showed that the Rev-erb-α(-/-) female mice were infertility, and the number of embryos of Rev-erb-α(-/-) females was less than that of Rev-erb-α(+/+) females. However, the follicle development of Rev-erb-α(-/-) female mice was normal. The estrous cycle of Rev-erb-α(-/-) female mice was 3.22 days longer than that of Rev-erb-α(+/+) female mice. The results suggest that loss of Rev-erb-α prolongs estrous cycle, which is probably one of the reasons for female mice infertility, and circadian rhythm is important for mammalian estrous cycle.
Animals ; Circadian Rhythm ; Estrous Cycle ; Female ; Fertility ; Litter Size ; Male ; Mice ; Mice, Inbred C57BL ; Mice, Knockout ; Nuclear Receptor Subfamily 1, Group D, Member 1 ; genetics ; physiology ; Pregnancy

The objective of this study was to investigate the effects of oxytocin infusion on corpus luteum (CL) function during early to mid-diestrus by measuring luteal size (LS) and luteal blood flow (LBF) along with plasma levels of progesterone (P4) and prostaglandin metabolites (13,14-dihydro-15-keto-prostaglandin F2alpha, PGFM). On day (D) 7 of the estrus cycle (D1 = ovulation), seven cows received 100 IU of oxytocin (OXY) or placebo (PL) following a Latin square design. LS and LBF increased in both groups over time and no differences were observed between the groups. PGFM did not differ either within the groups over time or between the groups at any time point. P4 of the OXY group was higher compared to that of the the PL group 360 min after the infusion (p = 0.01) and tended to be higher at the time points 450 min, 48 h, and 72 h (all p = 0.08). Results from this study support the hypothesis that OXY is not directly involved in the mechanism(s) governing blood flow of the CL and has no remarkable effects either on luteal size or P4 and PGFM plasma levels. Further investigation is needed to elucidate the role of OXY in CL blood flow during early and late luteal phases.
Animals ; Cattle/*physiology ; Corpus Luteum/blood supply/*drug effects/secretion/ultrasonography ; Dinoprost/analogs & derivatives/blood ; Estrous Cycle/*drug effects/physiology ; Female ; Immunoenzyme Techniques/veterinary ; Organ Size/physiology ; Oxytocin/*pharmacology ; Progesterone/blood/*secretion ; Random Allocation ; Ultrasonography, Doppler, Color/veterinary

Ectonucleotide pyrophosphatase/phosphodiestrase 2 (Enpp2) isolated from the supernatant of human melanoma cells is a lysophospholipase D that transforms lysophosphatidylcholine into lysophospatidic acid. Although multiple analyses have investigated the function of Enpp2 in the hypothalamus, its role in the uterus during the estrous cycle is not well understood. In the present study, rat uterine Enpp2 was analyzed by RT-PCR, Western blotting, and immunohistochemistry. Quantitative PCR analysis demonstrated that uterine Enpp2 mRNA was decreased during estrus compared to proestrus and diestrus. To determine whether uterine Enpp2 expression is affected by sex steroid hormones, immature rats were treated with 17beta-estradiol (E2), progesterone, or both on postnatal days 14 to 16. Interestingly, the expression of Enpp2 mRNA and protein were down-regulated by E2 in the uterus during estrus but not during proestrus or diestrus, suggesting that Enpp2 may play a role in uterine function during estrus. Enpp2 is primarily localized in the stromal cells of the endometrium during proestrus and estrus. During diestrus, Enpp2 was highly expressed in the epithelial cells of the endometrium. Taken together, these results suggest that uterine Enpp2 may be regulated by E2 and plays a role in reproductive functions during female rat development.
Animals ; Estradiol/pharmacology ; Estrous Cycle/*physiology ; Female ; Gene Expression Regulation/*physiology ; Immunohistochemistry ; Mifepristone/pharmacology ; Phosphoric Diester Hydrolases/genetics/*metabolism ; Progesterone/pharmacology ; RNA, Messenger/genetics/metabolism ; Rats ; Rats, Sprague-Dawley ; Uterus/*metabolism

OBJECTIVETo study the changes in endogenous neuregulin-1 (Nrg1) expression in the anterior pituitary of female Wistar-Furth rats in different phases of the estrous cycle.

METHODSFemale Wistar-Furth rats during estrous cycles were used. RT-PCR was employed to study the changes in the expression of Nrg1 isoforms and their cognate receptors ErbB-2 and ErbB-4 in the anterior pituitary in different phases of the estrous cycle. Western blotting was used to detect Nrg1 expression at the protein level. Immunofluorescence staining was used to identify hypophyseal cells expressing Nrg1 and observe the localization and distribution of Nrg1 and functional phosphorylation of ErbB-4. The co-expression of Nrg1 and ErbB-4 in the anterior pituitary of Rhesus monkey was also investigated.

RESULTSSome of the Nrg1 isoforms, especially type III Nrg1s, were expressed at a higher level during the estrous cycle I (E1) and estrous cycle II (E2), a result consistent with that of Western blotting for samples of the anterior pituitaries collected at these phases. Immunofluorescence staining identified the gonadotrophs as the main source of Nrg1, and showed an extensive distribution of Nrg1 in the anterior pituitary in E1 and E2 phases accompanied by apparent phosphorylated activation of ErbB-4. Adjacent distribution of Nrg1- and ErbB-4-positive cells was also observed in the anterior pituitary of male Rhesus monkeys.

CONCLUSIONOur results provide evidence for the expression of multiple Nrg1 isoforms and the presence of Nrg1/ErbB-4 signaling in the anterior pituitary of female Wistar-Furth rats. This signaling demonstrates an estrous cycle phase-related pattern. Additionally, Nrg1/ErbB-4-based juxtacrine signaling may exist in the anterior pituitary of male non-human primate.

Animals ; Estrous Cycle ; physiology ; Female ; Macaca mulatta ; Male ; Neuregulin-1 ; metabolism ; Phosphorylation ; Pituitary Gland ; metabolism ; Protein Isoforms ; metabolism ; Rats ; Rats, Inbred WF ; Receptor, Epidermal Growth Factor ; metabolism ; Receptor, ErbB-4