Administration Of Estradiol Benzoate Research Articles

Regulating effect of Gegen Decoction on hypothalamic-pituitary-ovarian axis in mice with primary dysmenorrhea

This study aimed to explore the regulating effect of Gegen Decoction(GGD) on the hypothalamic-pituitary-ovarian axis(HPOA) dysfunction in the mouse model of primary dysmenorrhea(PD). The mouse model of PD with periodic characteristics was established by administration of estradiol benzoate and oxytocin. Mice were randomized into control, model, GGD, and ibuprofen groups. The writhing response, hypothalamus index, pituitary index, ovary index, and uterus index were observed and determined. The serum levels of prostaglandin F_(2α)(PGF_(2α)), gonadotropin-releasing hormone(GnRH), follicle-stimulating hormone(FSH), luteinizing hormone(LH), and estrogen(E_2) levels were measured by ELISA kits. Western blot and qPCR were employed to determine the protein and mRNA levels, respectively, of gonadotropin-releasing hormone receptor(GnRH-R) in the pituitary tissue, follicle-stimulating hormone receptor(FSHR) and luteinizing hormone receptor(LHR) in the ovarian tissue, and estrogen receptor(ER) in the uterine tissue. The results showed that the writhing response, serum levels of PGF_(2α), GnRH, FSH, LH, and E_2, ovarian and uterine indexes, the protein and mRNA levels of GnRH-R in the pituitary tissue, FSHR and LHR in the ovarian tissue, and ER in the uterine tissue were significantly increased in the model group compared with those in the control group. GGD inhibited the writhing response, reduced the serum levels of PGF_(2α), GnRH, FSH, LH, and E_2, decreased the ovarian and uterine indexes, and down-regulated the protein and mRNA levels of GnRH-R in the pituitary tissue, FSHR and LHR in the ovarian tissue, and ER in the uterine tissue. The data suggested that GGD can regulate the HPOA and inhibit E_2 generation in the mice experiencing recurrent PD by down-regulating the expression of proteins and genes related to HPOA axis, thus exerting the therapeutic effect on PD.

Embryo yield and quality in superovulated Simmental donor cows following oral supplementation with different sources of omega-3 and omega-6 fatty acids

Owing to contradictory results with respect to the yield and quality of embryos after supplementation with omega-3 fatty acids, this study sought to determine the effect of an oral supplement containing sources of omega-3 and omega-6 fatty acids on the ovarian response and embryo quality after superovulation. Cows were allocated to receive one of three oral supplement regimens. In the control (CO) group (n = 9), cows were fed a control supplement without fatty acids. The cows in the soybean oil (SO) (n = 8) and linseed oil (LO) (n = 8) groups received supplements containing SO or LO, respectively. Supplements were administered for 28 days, commencing 7 days before the onset of estrus synchronization until the day of embryo collection. The estrous cycle of all cows was synchronized by inserting a controlled internal drug release (CIDR) device (progesterone 1.38 g), followed by the administration of estradiol benzoate 2.5 mg. The CIDR device was withdrawn 7 days after insertion, followed by intramuscular administration of dinoprost 25 mg. Superovulation was induced via the administration of 152 mg of follicle-stimulating hormone (Folltropin-V) in tapered doses, starting 72 h before CIDR withdrawal. The embryos were collected 6 days after artificial insemination. The estrous response, onset of estrus after CIDR withdrawal, and number of ovulations were similar among the experimental groups (p > 0.05). The mean number of transferable embryos (grades 1 and 2) was higher in the LO group compared to the CO group (9.0 vs 3.2; p < 0.05). Although the number of transferable embryos (grades 1 and 2) was greater in the LO group than that in the SO group, the difference was not statistically significant (9.0 and 4.4; p > 0.05). In conclusion, oral supplementation with LO for 28 days increased the yield of transferable embryos, which could potentially improve the profitability of embryo transfer programs in cattle.

Administration of Estradiol Benzoate Enhances Ovarian and Uterine Hemodynamics in Postpartum Dairy Buffaloes.

The postpartum (PP) period is a crucial stage for the resumption of reproductive performance and ovarian cyclicity in dairy buffaloes. The present study aimed, for the first time, to assess the effect of the administration of estradiol benzoate (EB) on ovarian and uterine hemodynamics in PP dairy buffaloes. Eight pluriparous acyclic domestic buffaloes were enrolled in the present experiment and received a dose of 10 mg of estradiol benzoate (EB) intramuscularly 4 weeks after parturition. All animals were examined two times before EB administration (days -3, and -1) and on the day of EB administration (day 0), followed by examinations on days 1, 3, 5, 7, and 9 post-EB administration. The middle uterine artery (MUA) and ovarian artery (OA) blood flow patterns were assessed using a color Doppler ultrasound device. The reproductive parameters were (1) the cross-sectional diameters (cm) of the OA and MUA, (2) cranial uterine horn thickness (UHT; cm), and (3) hemodynamic changes within the MUA on both the ipsi- and contra-lateral sides of the previous pregnant horn and within the OA corresponding to the ovarian tissues. The examined blood flow parameters were the pulsatility index (PI), resistance index (RI), peak systolic/end-diastolic ratio (S/D), time-averaged maximum velocity (TAV; cm/s), uterine blood flow rate (BFR; bpm), and uterine blood flow volume (BFV; mL/min). Concomitantly, blood samples were collected from the coccygeal vein, and the sera were stored at -18 °C for use in estradiol (E2-17β) and nitric oxide (NO) assays. The results revealed increases in both OA and MUA cross-sectional diameter (cm) on the ipsi-lateral and contra-lateral (p < 0.05) sides within 24 h until day 9 post-treatment. The values of the RI and PI of blood flow within the OA and MUA on the ipsi-lateral and contra-lateral sides of the previous pregnancy were obviously lower (p < 0.05) at 24 h after the administration of EB, and then, started to gradually elevate, reaching the pre-treatment values on day 9 after EB administration. Both the BFR and BFV in the OA and MUA significantly increased from 24 h to 72 h after EB administration on both the ipsi-lateral and contra-lateral sides (p < 0.05); then, their values started to decrease to reach the pretreatment value on day 9 after EB administration. Both E2 and NO concentrations significantly increased (p < 0.05) from 24 h until day 3 after EB injection and then started to decline after that, reaching the pre-treatment value on day 9. In conclusion, the administration of EB enhances the ovarian and uterine blood flow concomitantly with increased levels of NO in PP dairy buffaloes.

Development of social recognition ability in female rats: Effect of pubertal ovarian hormones

The ability to recognize previously encountered conspecifics is crucial for social interaction. This social recognition ability is well characterized in adult rodents of both sexes but remains largely unexplored in juveniles. Using the social discrimination test of social recognition with short intervals (30 min and 1 h), we first found that juvenile female rats do not display a difference in investigation directed toward a novel vs. familiar stimulus rat. Using the social discrimination test with a 30-minute interval, we then showed that social recognition is established by the time of adolescence in female rats. Based on these findings, we hypothesized that social recognition is dependent on the initiation of ovarian hormone release during puberty. To test this, we ovariectomized females prior to puberty and found that prepubertal ovariectomy prevented the development of social recognition ability in adulthood. Administration of estradiol benzoate, 48 h prior to testing, to juvenile females or prepubertally ovariectomized adult females did not restore social recognition, suggesting that ovarian hormones organize the neural circuitry regulating this behavior during adolescence. These findings provide the first evidence of an effect of pubertal development on social recognition ability in female rats and highlight the importance of considering sex and age when interpreting results from behavioral paradigms initially designed for use in adult males.

Estradiol and progesterone-induced lordosis behavior is modulated by both the Kisspeptin receptor and melanin-concentrating hormone in estradiol benzoate-primed rats

Intracerebroventricular (ICV) administration of estradiol benzoate (E2B) and progesterone (P) induces intense lordosis behavior in ovariectomized rats primed peripherally with E2B. The present study tested the hypothesis that the Kisspeptin (Kiss) and melanin-concentrating hormone (MCH) pathways regulate female sexual behavior induced by these steroid hormones. In Experiment 1, we tested the relevance of the Kiss pathway by ICV infusion of its inhibitor, kiss-234, before administration of E2B or P in estrogen-primed rats. Lordosis induced by E2B alone or with the addition of P was reduced significantly at 30, 120, and 240 min. In Experiment 2, ICV infusion of MCH 30 min before E2B or P significantly reduced lordosis in rats primed with E2B alone. These data support the hypothesis that the Kiss and MCH pathways, which can release or modulate gonadotropin-releasing hormone (GnRH), are involved in E2B- and P-induced lordosis.

Annona muricata Linn Stem Bark Protects against Uterine Proliferative Disorder Induced by Estradiol Benzoate in Female Rat

Aim: The opening of mitochondrial permeability transition (mPT) pore is an important event in the execution of mitochondrial-mediated apoptosis. Some bioactive compounds elicit their chemotherapeutic effects against tumor/cancer cells via the induction of mitochondrial-mediated apoptosis. Annona muricata, a medicinal plant, is folklorically used in the treatment of tumors and cancers. This study therefore aimed at investigating the effect of methanol stem bark extract of Annona muricata (MEAM) on apoptosis via mPT pore and estradiol benzoate (EB)-induced proliferative disorder using female Wistar rats.&#x0D; Methodology: Mitochondria were isolated using differential centrifugation. The mPT pore opening, cytochrome c release and mitochondrial ATPase activity were determined spectrophotometrically. The levels of estrogen (E2), luteinizing hormone (LH), follicle stimulating hormone (FSH), malondialdehyde (MDA) and activities of superoxide dismutase (SOD), glutathione peroxidase (GSH), were determined using ELISA technique. Histological and histochemical assessments of the uterine sections were carried out using standard methods. Phytochemical constituents of MEAM were determined using Gas Chromatography-Mass Spectroscopy (GC-MS).&#x0D; Results: The in vitro results showed a significant induction of mPT pore opening, release of cytochrome c and enhancement of mitochondrial ATPase (mATPase) activity in a concentration-dependent manner. However, oral administration of MEAM did not induce rat uterine mPT pore opening, neither any significant release of cytochrome c nor enhancement of mATPase activity at the dosages used. Interestingly, MEAM reversed the EB-induced increase in E2, LH and FSH. The MEAM also improved the antioxidant milleu by reducing MDA level and increasing the SOD and GSH-Px activities in the treatment groups. Administration of EB induced endometrial hyperplasia in the model group which was mitigated by MEAM in the treatment group. The GC-MS analysis of MEAM revealed the presence of some important phytochemicals that are pharmacological relevant in cancer treatment.&#x0D; Conclusions: This study suggests that the methanol stem bark extract of Annona muricata contains bioactive compounds that protect against EB-induced uterine proliferative disorder in female Wistar rats.

EFECTO DE LA EXPRESIÓN DE CELOS Y LA ADICIÓN DE GnRH SOBRE LA TASA DE PREÑEZ EN VACAS HOLSTEIN EN LACTANCIA SINCRONIZADAS CON ESTRADIOL Y DISPOSITIVOS CON PROGESTERONA

The aim of this investigation was to evaluate the effect of the addition of GnRH at the beginning and end of a treatment with progesterone-releasing devices (P 4 ) and estradiol (E2) and the expression of estrus on pregnancy rates (PR) of lactating dairy cows inseminated at fixed time (FTAI). The estrus synchronization treatment consisted on the insertion of a P 4 device for 8 days and the administration of estradiol benzoate (EB) on the day of insertion and estradiol cypionate (ECP) at the time of device removal to induce ovulation. Experiment 1 was designed to determine whether the addition of GnRH at the start of the protocol improved the PR and if the division of the time of artificial insemination (AI) improved PR. The addition of GnRH on Day 0 did not improve PR (44% vs 40%) but the AI of cows showing estrus at 48 h and the administration of GnRH at 48 h and AI at 60 h of those not showing estrus resulted in higher PR than those cows that were FTAI at 48 h, regardless of estrus expression (53% vs 31%; P &lt;0.01). Experiment 2 was designed to study follicular dynamics and assess whether the PR varies using different times of AI (48 h vs 60 h), according to the expression of estrus. The division of AI and adding GnRH at 48 h decreased the dispersion in the interval between AI and ovulation. There was an interaction (P&lt;0.05) between the time of AI and expression of estrus. Pregnancy rates were higher in cows in estrus at 48 h that were AI at that time (47.8%) and those that were not in heat at 48 h and were AI at 60 h (53.4%) than those who were not in estrus at 48 h and were FTAI at that time (19.4%) and those that were in estrus at 48 h and were FTAI at 60 h (29.7%). In Experiment 3 PR was evaluated based on the addition or not of GnRH to cows not showing estrus at 48 h. Pregnancy rate was higher (P&lt;0.05) in cows that were not in estrus at 48 h, that received GnRH at that time and were AI at 60 h than in cows not showing estrus and 48 h that were also AI at 60 h but without GnRH (56.0% vs 39.8%). Experiment 4 evaluated factors that may affect PR in cows treated with the protocol developed in this experiment. It was found that the heat stress of January, a body condition score &lt;2.75 and the presence of only small follicles (&lt;10 mm and without CL) adversely affect PR. In conclusion, the results of this series of experiments confirm the hypothesis that the inclusion of a dose of GnRH and the modification of the time of AI increase PR in lactating dairy cows treated with P 4 devices and estradiol that does not express estrus at the time of FTAI.

Eficiência e acurácia de diferentes indutores de ovulação após a remoção do dispositivo de progesterona em vacas mestiças multíparas

Abstract The aim of this study was to verify the efficiency and ovulation time after the administration of different inducers for synchronization of ovulation in beef cows. One hundred and eight non-lactating cows were distributed into the control group (CG; untreated; n=28), estradiol benzoate (EB) group (EBG; n=28); 17 beta-estradiol (17ßE) group (17ßEG; n=28), and deslorelin (DES) group (DESG; n=24). On day minus 11 (D-11) of the protocol, the CG underwent application of cloprostenol and ultrasound examination (US); on D0, progesterone (P4) was inserted plus EB; on D7, cloprostenol was applied; on D9, P4 was removed and cloprostenol plus 400 IU of equine chorionic gonadotropin (eCG) was injected. The EBG was subjected to treatment identical to that of the CG, except on D10, when the cows received EB. The 17ßE was subjected to the same protocol used in the CG except for the administration of 17ßE on D10. And, the DESG was subjected to the same treatment as the CG, except on D10, when the group received DES acetate. Twelve hours after the administration of EB, 17ßE and DES, ovarian US were performed every 6 hours. The preovulatory follicle (POF) diameters measured before ovulation were 19.5; 14.7; 18.7 and 19.8 mm respectively for CG, EBG, 17ßEG and DESG; and the time intervals between inducer application and ovulation were 20.2; 18.9; 21.0 and 22.5 hours respectively. In conclusion, all ovulation inducers were efficient in promoting ovulation; the inducers caused ovulation between 18.9 and 22.5 hours; EB promoted ovulation in a shorter time (P&lt;0.05); 17ßE and DES showed greater variation in application/ovulation time between groups.

PHYTOCHEMICAL SCREENING AND APHRODISIAC EFFECT OF ETHANOLIC EXTRACT OF MASSULARIA ACUMINATA(G. DON) BULLOCK EX HOYL. (RUBIACEAE)IN MALE WISTAR RATS

Objective: The objective of the present study is to determine, through phytochemical screening, the major chemical compounds and to evaluate the aphrodisiac effect of the ethanolic extract of M.acuminata stems in adult male rats. Methods :To achieve our objectives, a phytochemical study was conducted to determine the major chemical compounds present in the ethanolic extract of M. acuminatastems. The phytochemical screening was carried out following standard analytical procedures using thin layer chromatography.The aphrodisiac effect was evaluated in sexually naïve male rats. In sexually naïve male rats, a single administration of the ethanolic extract was performed at doses of 10, 20 and 40 mg/kg versus 0.5 mL/100g distilled water and 715 µg/kg Sildenafil Pfizer 50 mg in the negative and positive control rats, respectively. Female rats were induced to oestrus by sequential administration of estradiol benzoate (Sigma - Aldrich) (25 μg/rat) to make them receptive to males. Results :The results of the phytochemical screening revealed that the ethanolic extract of M. acuminata stems contains coumarins, flavonoids, tannins, triterpenes of triterpenesaponins. The biological study showed that at doses of 20 and 40 mg/kg, ethanolic extract of M. acuminatastems resulted in a significant (p &lt; 0.05) and highly significant (p &lt; 0.001) increase in the number of sexual mounts, the number of erections, the number of ejaculations and a significant (p &lt; 0.01) decrease in the latency time between sexual mounts in male rats. Conclusions:The sexual stimulating effects of the ethanolic extract of M. acuminata observed in this study could be attributed to the presence of the identified chemical compounds, hence the interest in using this plant in traditional aphrodisiac medicine.

Estrogens influence differentially on the pelvic floor muscles activation at somatovisceral reflexes involved in micturition of rabbits.

To determine the estrogen-dependency of the bladder and urethral function and the coordinated activation of pelvic floor muscles (PFM) during micturition. We allocated age-matched female rabbits to control, 1-month ovariectomized (OVX), and OVX plus 2-week estradiol benzoate (EB) groups to record cystometry, urethral pressure, and electromyograms of bulbospongiosus (Bsm), and pubococcygeus muscles (Pcm) simultaneously. We also measured serum estradiol levels and myofiber cross-sectional area. We assessed urodynamic and urethral variables, categorized the Bsm-Pcm activation patterns at storage and voiding phases, and obtained the power spectrum density of muscle activation around the voiding phase. We investigated the influence of ovarian hormones, in general, and the contribution of estrogen, particularly on the functions of the bladder, urethra, and PFM. Statistical significance was set at P < 0.05. Ovarian hormones influence the bladder, urethral, and PFM functions. The urodynamics analyses indicated estrogens contribute to voiding duration and, to a lesser extent, to the time between bladder contractions. Urethral pressure at closure (maximal pressure-to-maximal urethral pressure ratio) improved partially (8%, P < 0.05) in the OVX plus 2-week estradiol benzoate compared with OVX, but urethral resistance increased (∼1.9-fold, P < 0.05) compared with control rabbits. Our findings support that Pcm activity at voiding is estrogen-sensitive, albeit EB administration reduced it at storage resume, which relates to high urethral resistance. Ovariectomy impairs bladder and urethral pressures and Bsm and Pcm activation at micturition in anesthetized rabbits. Estrogen administration partially reverts some of these effects and influences Pcm activation.

Effects of administration of exogenous estradiol benzoate on follicular, luteal, and uterine hemodynamics in beef cows

Objectives of these two experiments were to determine if exogenous estradiol benzoate (EB) affects follicular, luteal, and uterine hemodynamics. In both experiments, 77 estrous-synchronized beef cows were assigned to one of two treatments: 1) Control (CON) or, 2) an injection of 1 mg EB the day before expected estrus (Day 0; Experiment 1) or on the day of estrus (Day 1; Experiment 2). There was transfer of an embryo (Day 7) into cows that expressed estrus. In Experiment 1, estradiol concentrations in circulation at Day 0 were greater in EB-treated cows (P = 0.003); however, concentrations of progesterone were only greater (P = 0.03) at Day 21 in cows of the EB-treated compared to those in the CON group. The follicular and luteal blood perfusion was similar, however, treatment with EB resulted in a greater uterine blood perfusion. In Experiment 2, treatment with EB did not affect size or blood perfusion of the corpus luteum (CL) on Day 7, 14, and 21. Only on Day 21, however, did pregnant cows have a larger CL than non-pregnant cows (P = 0.02). Blood perfusion to the CL was greater (P < 0.05) in all cows on Day 21 compared to 7 or 14 and those determined to be pregnant on Day 35 tended (P = 0.06) to have greater CL blood perfusion only on Day 21 compared to non-pregnant cows. In conclusion, EB treatment resulted in a greater blood perfusion of the uterus, and only affected the CL on Day 21 in Experiment 2.

Heterologous beta-nerve growth factor (β-NGF) given at the LH surge enhances luteal function in dairy heifers

Genetic selection for high yield milk production has led to a decline in dairy cattle's reproductive performance over the last 40 years. Low progesterone (P4) plasma content following ovulation is associated with suboptimal fertility in dairy cattle. Several pieces of evidence indicate that the protein beta-nerve growth factor (β-NGF) that is present in the male seminal plasma exerts potent ovulatory and luteotrophic effects following systemic administration in camelids but also in other species. In this study, we determine whether systemic administration of purified llama β-NGF given at the induced preovulatory luteinizing hormone (LH) peak improves corpus luteum (CL) function in dairy heifers subjected to an estradiol (E2) / P4 estrus-synchronization protocol. To achieve this, we first determined plasma E2 and LH hormone profiles to establish the timing of the estradiol benzoate (EB)-induced LH peak in estrus-synchronized heifers. Then, we tested whether the administration of β-NGF given at the end of this peak affects the CL and its function by analyzing diameter, vascular area, and P4 output. Our results show that, with the estrus-synchronization protocol applied, plasma LH concentrations peaked (P < 0.01) 40-h and 16-h after removal of the bovine intravaginal device (DIB; containing 1.0 g of P4) plus cloprostenol injection and subsequent EB administration, respectively; after peaking, plasma LH concentrations remained stable for the next 8-h to then return to basal levels. Heifers synchronized with this protocol and receiving a dose of 1 mg of β-NGF at the end of the LH peak (ie, 48-h after DIB removal) did not show significant differences in CL diameter, but these exhibited a greater CL vascular area (P = 0.01) than the observed in vehicle-injected heifers. Furthermore, plasma P4 concentration in β-NGF-treated heifers was higher (P = 0.001) than those quantified in vehicle-injected heifers. These results support the use of β-NGF in estrus-synchronization protocols to improve the early luteal function in dairy heifers.

Dinámica folicular y relación cortisol-respuesta ovulatoria en vacas tratadas con diferentes cantidades de progesterona

El objetivo del presente estudio fue evaluar si el tratamiento con dispositivos intravaginales (DIV) con diferentes cantidades de progesterona (P4) afectaba la concentración plasmática de dicha hormona, la dinámica folicular y el porcentaje de ovulación en vacas. Además, se fijó como objetivo secundario ver si existía relación entre el nivel plasmático de cortisol y la respuesta ovulatoria. Vacas secas, cíclicas, Bos taurus, fueron asignadas aleatoriamente a 3 grupos que recibieron los siguientes tratamientos: 1) T0,558 (n=10), en el día 0 se colocó un DIV con 0,558 g de progesterona más benzoato de estradiol (BE). En el día 8 se retiró el dispositivo y se administró D-cloprostenol. En el día 9 se administró BE. 2) T1 (n=10) y T1,3 (n=10), similares al grupo T0,558, con la salvedad que se utilizó un DIV con 1 g y 1,3 g de P4, respectivamente. No se observaron efectos del tratamiento sobre el porcentaje de ovulación (66,7%), diámetro del folículo dominante ovulatorio y niveles de P4 plasmática. La concentración de cortisol en plasma fue mayor en las vacas que no ovularon. Se concluye que la cantidad de P4 contenida en los DIV evaluados no afecta la concentración de dicha hormona en plasma ni la dinámica folicular. El nivel de cortisol se relaciona con la respuesta ovulatoria y éste podría ser un indicador de estrés, el cual podría afectar la eficiencia reproductiva.

Melatonin inhibits cell proliferation in a rat model of breast hyperplasia by mediating the PTEN/AKT pathway.

In the present study, a rat model of breast hyperplasia was established via the administration of estradiol benzoate and progesterone. Subsequent changes associated with breast hyperplasia were then investigated by measuring the diameter and height of the nipples and by staining breast tissue with hematoxylin and eosin. The proliferation and apoptosis of hyperplastic cells in the breast tissue were then determined by analyzing the expression of proliferating cell nuclear antigen (PCNA) and cleaved-caspase-3 by immunohistochemistry and TUNEL staining. We also determined the expression of proteins associated with the phosphatase and tensin homolog (PTEN)/protein kinase B (AKT) signaling pathway by western blotting. Melatonin treatment led to a significant reduction in the degree of breast hyperplasia (P<0.05), a significant reduction in PCNA, a significant increase in the level of apoptosis (P<0.05), a significant increase in PTEN (P<0.05), and a significant reduction in AKT/p-AKT (P<0.05). Furthermore, melatonin significantly decreased the aggravation of breast hyperplasia induced by application of a PTEN inhibitor. Melatonin reduced the degree of breast hyperplasia, reduced the proliferation of hyperplastic breast tissue cells, and promoted cell apoptosis in hyperplastic tissue. These effects were achieved by the specific regulation of proteins in the PTEN/PI3K/AKT axis.

Induction of short-term pseudopregnancy in gilts by the administration of estradiol benzoate or estradiol dipropionate to achieve ovulatory synchronization for embryo collection.

A study was conducted to investigate whether ovulation in gilts could be synchronized for embryo collection by the administration of estradiol benzoate (EB) or estradiol dipropionate (EDP) to induce pseudopregnancy, followed by the treatment with prostaglandin F2α (PGF2α ) on 10days after. Ten gilts each received a total of 20mg of EB or EDP on Day 10 or EB on Day 10 and 14 to induce pseudopregnancy (Day 0=onset of estrus). Donors received PGF2α 10 or 15days (as a control) after the first administration of estrogens and subsequently eCG and hCG, and were then inseminated artificially. The embryos were collected 7days after the administration of hCG, and assessed for embryo yield and their developmental stages. All protocols resulted in good embryo yield (9.8-13.2 embryos in average), and the embryos showed average ability to develop to the expanded blastocyst stage (3.29-4.03 as developmental scores) without any significant differences among the protocols. These results suggest that the administration of PGF2α 10days after the treatment of gilts with EB or EDP would allow synchronization of ovulation and embryo collection, as well as shortening the period from estrus detection to embryo collection, thus improving embryo collection efficiency.

Intravaginal administration of estradiol benzoate capsule for estrus synchronization in goats.

Estrus synchronization requires multiple treatments of hormonal drugs, requiring considerable time and cost. The aim of the present study was to develop an estrus synchronization protocol using intravaginal administration of estradiol benzoate (EB) capsules in goats. Two types of capsules were prepared: an EB capsule that melted immediately after administration and a sustained-release (SR) EB capsule that dissolved slowly and reached a peak after 24 h. Goats with functional corpus lutea were intramuscularly treated with prostaglandin F2α (PG). At 24 h after PG administration, goats were administered 1 mg of EB solution intramuscularly (PG + 24IM; n = 6) or 1 mg of EB capsule intravaginally (PG + 24EB; n = 6). The SR EB capsule was administered intravaginally at the time of PG administration (PG + SR; n = 6). The control group (n = 6) received only PG. All groups showed estrus within 72 h after PG administration. The onset of estrus did not differ significantly between the PG + 24IM and PG + SR groups but was earlier than in the control group. Estradiol concentration in the PG + SR group peaked at 11.5 ± 6.1 h after EB and PG administration. Peak estradiol concentrations were not significantly different between the PG + 24IM and PG + SR groups (78.0 ± 25.8 and 64.0 ± 38.1 pg/ml, respectively), and were higher than the PG + 24EB and control groups (27.3 ± 8.8 and 14.6 ± 6.1 pg/ml, respectively). These results suggest that intravaginal administration of an EB capsule with a sustained-drug release base is applicable for estrus synchronization, as an alternative to intramuscular administration.

The Therapeutic Effect of Ge-Gen Decoction on a Rat Model of Primary Dysmenorrhea: Label-Free Quantitative Proteomics and Bioinformatic Analyses.

Ge-Gen decoction (GGD) is widely used for the treatment of primary dysmenorrhea (PD) in China. However, the mechanisms that underlie this effect are unclear. We investigated the protective mechanism of GGD in a rat model of PD using label-free quantitative proteomics. The model was established by the administration of estradiol benzoate and oxytocin. Thirty rats were divided into three groups (ten rats/group): a control group (normal rats), a model group (PD rats), and a treatment group (PD rats treated with GGD). The serum levels of prostaglandin E2 (PGE2) and prostaglandin F2α (PGF2α) were measured by ELISA. Nanohigh-performance liquid chromatography-tandem mass spectrometry (nano-HPLC-MS/MS) was used to identify differentially expressed proteins (DEPs), and bioinformatics was used to investigate the protein function. Proteomic data were validated by western blot analysis. Oxytocin-induced writhing responses and abnormal serum levels of PGE2 and PGF2α were reversed following the administration of GGD. A total of 379 DEPs were identified; 276 were identified between the control group and the model group, 144 were identified between the model group and the treatment group, and 41 were identified as DEPs that were common to all groups. Bioinformatics revealed that the DEPs between the control group and the model group were mainly associated with cellular component biogenesis and binding processes. The DEPs between the model group and the treatment group were mainly involved in the protein binding and metabolic process. The expression levels of HSP90AB1 and the phosphorylation levels of ERK, JNK, and P-p38 in the uteri of rats in the three groups were consistent with the proteomic findings; MAP kinases (ERK, JNK, and p38) are known to be involved in the production of inflammatory cytokines and oxytocin signaling while HSP90AB1 is known to be associated with estrogen signaling. Collectively, these data indicate that GGD may exert its protective function on PD by regulating the inflammatory response and signaling pathways associated with oxytocin and estrogen.

Estradiol benzoate priming during induction of estrus with Vitex-castus extract in dogs

This study compared two methods of estrus induction between dogs (using vitagnus and vitagnus-estradiol). A total of 10 adult cyclic female Shih tzu Terrier mix breed dogs at anestrus stage were selected and divided into two groups. The first group (VAC) received vitagnus for five weeks (90 mg daily, PO). The second group (VAC-E2) was treated with vitagnus and estradiol benzoate. Estradiol benzoate was injected at the beginning of each week (0.01 mg/kg, IM). Blood sampling for evaluation of steroid hormones and vaginal smears were taken weekly. The sings and return to the estrus with the number of puppies were recorded. In the VAC group, 60%, and in the VAC-E2 group, 80% of dogs returned to the follicular phase after five weeks. In the VAC-E2 group, signs of estrus appeared 7 to 10 days and a mating process started 4 to 6 days earlier than those in the VAC group. The average number of delivered puppies was 4. These symptoms were confirmed by the cytology of the vagina. There was no significant difference in the estradiol and progesterone levels between groups. The mean concentration of estradiol significantly changed between weeks 1 and 4, 1 and 5, and 2 and 5 (p < 0.05). The progesterone level in the VAC-E2 group on week five was higher than that in other weeks. In conclusion, the administration of estradiol benzoate before vitagnus improved induction of estrus in dogs.

ESTRADIOL AND GNRH ON OVULATION INDUCTION FOR ESTRUS SYNCHRONIZED CROSSBRED COWS1

ABSTRACT Estradiol benzoate (EB), estradiol cypionate (EC), and gonadotrophin releasing hormone (GnRH) were evaluated as ovulation inducers for TAI of crossbred lactating cows. In experiment I (n = 45), the follicular dynamics was evaluated, while in experiment II (n = 171) the reproductive efficiency was evaluated. All females were submitted to a synchronization protocol: insertion on day 0 (D0) of intravaginal progesterone -release intravaginal device (PRID; 1g) plus administration of EB 2mg; D8, PRID removal, administration of 0.150mg PGF2α and 400 IU of eCG, and cows were allocated into three treatments: 1) TEB9 - IM administration of 1mg EB on D9 and AI performed 52 hours after PRID removal; 2) TEC - IM administration of 1mg EC on D8 and AI performed 48 hours after withdrawal of PRID; and 3) TGnRH - administration of 100pg GnRH on D10 and AI performed 52 hours after removal of PRID. The follicular growth rate was lower in the EC group (p &lt;0.05). There was no effect of treatments on ovulation and pregnancy rates (p &gt;0.05). The use of EB, EC, and GnRH as ovulation inducers in the TAI protocol did not show marked differences in the evaluated patterns of follicular dynamics and pregnancy.

Administering an additional prostaglandin F2α injection to Bos indicus beef cows during a treatment regimen for fixed-time artificial insemination

Two experiments were conducted to evaluate if an additional prostaglandin F2α (PG) injection during an estradiol-based estrous synchronization treatment regimen affects pregnancy rates resulting from fixed-time artificial insemination (FTAI) in Nelore cows. In Experiment 1, 1039 cows were administered estradiol benzoate and an intravaginal progesterone releasing device (CIDR) on d -11, an injection of PG on d -4, with CIDR removal and administration of estradiol cypionate and eCG occurring on d -2, and FTAI on d 0. Cows were administered an additional injection of PG (PG2) or saline (PG1) on d -2. Percentage pregnancy per FTAI on d 30 was greater (P = 0.01) in cows of the PG2 than PG1 group (54.5 % and 46.6 %, respectively). In Experiment 2, there was use of the same treatment regimen for estrous synchronization of 934 cows as that for Experiment 1 followed by FTAI, with there being diagnosis of whether cows had or did not have a corpus luteum on d -4. Response to estrous synchronization, largest follicle diameter at FTAI, and pregnancy per FTAI were greater (P ≤ 0.05) in cows of the PG2 than PG1 group with a body condition score (BCS) < 5.0 at FTAI (81.2 % and 72.6 %, 11.9 and 11.2 mm, 55.5 and 45.6 %; respectively). These treatment responses did not differ (P ≥ 0.18) in cows with BCS ≥ 5.0. Collectively, results indicate that treatment with PG2 increased pregnancy per FTAI in B. indicus cows deficient in body energy reserves, by enhancing follicle development and estrous synchronization response.