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Zhiping Gu - One of the best experts on this subject based on the ideXlab platform.
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effects of droloxifene on apoptosis and bax bcl 2 protein expression of luteal cells in pseudopregnant rats
Acta Pharmacologica Sinica, 2001Co-Authors: Ying Leng, Zhiping GuAbstract:Aim: To study the effects of droloxifene on apoptosis and the expression of Bax and Bcl-2 protein in corpus luteum of pseudopregnant rats. Methods: HE staining was used to examine the histological changes of ovaries. Apoptosis detection in situ was performed with TUNEL method. Expression of Bax and Bcl-2 protein was observed by immunohistochemistry analysis. Results: Apoptosis of luteal cells during the spontaneous regression of corpus luteum of pseudopregnant rats appeared on d 13 of Pseudopregnancy, and the marked increase of apoptotic luteal cells could be observed on d 15. When pseudopregnant rats were treated with droloxifene 20 mg . Kg on d 2, apoptosis of luteal cells could be observed on d 8 and the duration of Pseudopregnancy could be shortened from (15.5 +\- 1.1) d to (12.8 +\- 1.6) d. In pseudopregnant rats, the expression of Bax and Bcl-2 protein was found in the cytoplasm of luteal cells. However, no obvious differences in the intensity or localization could be found during various days of the Pseudopregnancy, while an increase in Bax and a decrease in Bcl-2 protein expression could be induced by droloxifene treatment. Conclusion: Droloxifene could facilitate apoptosis of luteal cells in pseudopregnant rats and shorten the period of Pseudopregnancy. An increased Bax/Bcl-2 ratio might be involved in the facilitation of apoptosis induced by droloxifene in corpus luteum of pseudopregnant rats.
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effects of droloxifene on apoptosis and bax bcl 2 protein expression of luteal cells in pseudopregnant rats
Acta Pharmacologica Sinica, 2001Co-Authors: Ying Leng, Ying Feng, Zhiping GuAbstract:Aim: To study the effects of droloxifene on apoptosis and the expression of Bax and Bcl-2 protein in corpus luteum of pseudopregnant rats. Methods: HE staining was used to examine the histological changes of ovaries. Apoptosis detection in situ was performed with TUNEL method. Expression of Bax and Bcl-2 protein was observed by immunohistochemistry analysis. Results: Apoptosis of luteal cells during the spontaneous regression of corpus luteum of pseudopregnant rats appeared on d 13 of Pseudopregnancy, and the marked increase of apoptotic luteal cells could be observed on d 15. When pseudopregnant rats were treated with droloxifene 20 mg . Kg on d 2, apoptosis of luteal cells could be observed on d 8 and the duration of Pseudopregnancy could be shortened from (15.5 +\- 1.1) d to (12.8 +\- 1.6) d. In pseudopregnant rats, the expression of Bax and Bcl-2 protein was found in the cytoplasm of luteal cells. However, no obvious differences in the intensity or localization could be found during various days of the Pseudopregnancy, while an increase in Bax and a decrease in Bcl-2 protein expression could be induced by droloxifene treatment. Conclusion: Droloxifene could facilitate apoptosis of luteal cells in pseudopregnant rats and shorten the period of Pseudopregnancy. An increased Bax/Bcl-2 ratio might be involved in the facilitation of apoptosis induced by droloxifene in corpus luteum of pseudopregnant rats.
Andrew J Kouba - One of the best experts on this subject based on the ideXlab platform.
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use of urinary 13 14 dihydro 15 keto prostaglandin f2α pgfm concentrations to diagnose pregnancy and predict parturition in the giant panda ailuropoda melanolecua
PLOS ONE, 2018Co-Authors: Beth M Roberts, Janine L Brown, David C Kersey, Rebecca J Snyder, Barbara S Durrant, Andrew J KoubaAbstract:Pregnancy determination is difficult in the giant panda (Ailuropoda melanolecua), representing a challenge for ex situ conservation efforts. Research in other species experiencing Pseudopregnancy indicates that urinary/fecal concentrations of 13,14, dihydro-15-keto-prostaglandin F2α (PGFM) can accurately determine pregnancy status. Our objective was to determine if urinary PGFM concentrations are associated with pregnancy status in the giant panda. Urinary PGFM concentrations were measured in female giant pandas (n = 4) throughout gestation (n = 6) and Pseudopregnancy (n = 4) using a commercial enzyme immunoassay. Regardless of pregnancy status, PGFM excretion followed a predictable pattern: 1) baseline concentrations for 11–19 weeks following ovulation; 2) a modest, initial peak 14–36 days after the start of the secondary urinary progestagen rise; 3) a subsequent period of relatively low concentrations; and 4) a large, terminal peak at the end of the luteal phase. Pregnant profiles were distinguished by an earlier initial peak (P = 0.024), higher inter-peak concentrations (P < 0.001), and a larger terminal peak (P = 0.003) compared to Pseudopregnancy profiles. Parturition occurred 23 to 25 days from the initial PGFM surge and within 24 hours of the start of the terminal increase. These pattern differences indicate that urinary PGFM monitoring can be used to predict pregnancy status and time parturition in the giant panda. Furthermore, this is the only species known to exhibit a significant PGFM increase during Pseudopregnancy, suggesting a unique physiological mechanism for regulating the end of the luteal phase in the giant panda.
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the acute phase protein ceruloplasmin as a non invasive marker of Pseudopregnancy pregnancy and pregnancy loss in the giant panda
PLOS ONE, 2011Co-Authors: Erin L Willis, David C Kersey, Barbara S Durrant, Andrew J KoubaAbstract:After ovulation, non-pregnant female giant pandas experience Pseudopregnancy. During Pseudopregnancy, non-pregnant females exhibit physiological and behavioral changes similar to pregnancy. Monitoring hormonal patterns that are usually different in pregnant mammals are not effective at determining pregnancy status in many animals that undergo Pseudopregnancy, including the giant panda. Therefore, a physiological test to distinguish between pregnancy and Pseudopregnancy in pandas has eluded scientists for decades. We examined other potential markers of pregnancy and found that activity of the acute phase protein ceruloplasmin increases in urine of giant pandas in response to pregnancy. Results indicate that in term pregnancies, levels of active urinary ceruloplasmin were elevated the first week of pregnancy and remain elevated until 20–24 days prior to parturition, while no increase was observed during the luteal phase in known pseudopregnancies. Active ceruloplasmin also increased during ultrasound-confirmed lost pregnancies; however, the pattern was different compared to term pregnancies, particularly during the late luteal phase. In four out of the five additional reproductive cycles included in the current study where females were bred but no birth occurred, active ceruloplasmin in urine increased during the luteal phase. Similar to the known lost pregnancies, the temporal pattern of change in urinary ceruloplasmin during the luteal phase deviated from the term pregnancies suggesting that these cycles may have also been lost pregnancies. Among giant pandas in captivity, it has been presumed that there is a high rate of pregnancy loss and our results are the first to provide evidence supporting this notion.
Ying Leng - One of the best experts on this subject based on the ideXlab platform.
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effects of droloxifene on apoptosis and bax bcl 2 protein expression of luteal cells in pseudopregnant rats
Acta Pharmacologica Sinica, 2001Co-Authors: Ying Leng, Zhiping GuAbstract:Aim: To study the effects of droloxifene on apoptosis and the expression of Bax and Bcl-2 protein in corpus luteum of pseudopregnant rats. Methods: HE staining was used to examine the histological changes of ovaries. Apoptosis detection in situ was performed with TUNEL method. Expression of Bax and Bcl-2 protein was observed by immunohistochemistry analysis. Results: Apoptosis of luteal cells during the spontaneous regression of corpus luteum of pseudopregnant rats appeared on d 13 of Pseudopregnancy, and the marked increase of apoptotic luteal cells could be observed on d 15. When pseudopregnant rats were treated with droloxifene 20 mg . Kg on d 2, apoptosis of luteal cells could be observed on d 8 and the duration of Pseudopregnancy could be shortened from (15.5 +\- 1.1) d to (12.8 +\- 1.6) d. In pseudopregnant rats, the expression of Bax and Bcl-2 protein was found in the cytoplasm of luteal cells. However, no obvious differences in the intensity or localization could be found during various days of the Pseudopregnancy, while an increase in Bax and a decrease in Bcl-2 protein expression could be induced by droloxifene treatment. Conclusion: Droloxifene could facilitate apoptosis of luteal cells in pseudopregnant rats and shorten the period of Pseudopregnancy. An increased Bax/Bcl-2 ratio might be involved in the facilitation of apoptosis induced by droloxifene in corpus luteum of pseudopregnant rats.
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effects of droloxifene on apoptosis and bax bcl 2 protein expression of luteal cells in pseudopregnant rats
Acta Pharmacologica Sinica, 2001Co-Authors: Ying Leng, Ying Feng, Zhiping GuAbstract:Aim: To study the effects of droloxifene on apoptosis and the expression of Bax and Bcl-2 protein in corpus luteum of pseudopregnant rats. Methods: HE staining was used to examine the histological changes of ovaries. Apoptosis detection in situ was performed with TUNEL method. Expression of Bax and Bcl-2 protein was observed by immunohistochemistry analysis. Results: Apoptosis of luteal cells during the spontaneous regression of corpus luteum of pseudopregnant rats appeared on d 13 of Pseudopregnancy, and the marked increase of apoptotic luteal cells could be observed on d 15. When pseudopregnant rats were treated with droloxifene 20 mg . Kg on d 2, apoptosis of luteal cells could be observed on d 8 and the duration of Pseudopregnancy could be shortened from (15.5 +\- 1.1) d to (12.8 +\- 1.6) d. In pseudopregnant rats, the expression of Bax and Bcl-2 protein was found in the cytoplasm of luteal cells. However, no obvious differences in the intensity or localization could be found during various days of the Pseudopregnancy, while an increase in Bax and a decrease in Bcl-2 protein expression could be induced by droloxifene treatment. Conclusion: Droloxifene could facilitate apoptosis of luteal cells in pseudopregnant rats and shorten the period of Pseudopregnancy. An increased Bax/Bcl-2 ratio might be involved in the facilitation of apoptosis induced by droloxifene in corpus luteum of pseudopregnant rats.
M A Diekman - One of the best experts on this subject based on the ideXlab platform.
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maternal recognition of pregnancy in swine ii plasma concentrations of progesterone and 13 14 dihydro 15 keto prostaglandin f2 alpha during the estrous cycle and during short and long Pseudopregnancy in gilts
Biology of Reproduction, 1996Co-Authors: Anthony E Pusateri, Matthew E Wilson, M A DiekmanAbstract:Two experiments were conducted to determine plasma progesterone (P4) and 13,14-dihydro-15-keto-prostaglandin F2 alpha (PGFM) concentrations in unmated gilts induced to have either short Pseudopregnancy (SPP) or long Pseudopregnancy (LPP). In experiment 1, estradiol-17 beta (E2) was injected on different combinations of days between Days 11 and 16 of the estrous cycle. For gilts induced to exhibit SPP, the interestrous interval averaged 27.0 +/- 0.4 days compared to the control interval of 20.0 +/- 0.4 days. In experiment 2, E2 injections were given on Days 12 and 13 or on Days 12 through 25. Interestrous intervals in SPP and nonpseudopregnant gilts were 25.6 +/- 0.2 and 19.9 +/- 0.6 days, respectively. Four of six gilts treated with E2 on Days 12-25 were induced to have LPP lasting more than 100 days. In both experiments, plasma P4 declined to baseline approximately 3 days before posttreatment estrus, regardless of type of Pseudopregnancy induced. Plasma PGFM peaked 4-6 days before posttreatment estrus in gilts displaying each type of response. In gilts exhibiting LPP, plasma PGFM concentrations tended to increase steadily during Pseudopregnancy. These data suggest that the mechanisms of luteolysis during the estrous cycle of unmated gilts and during estrogen-induced SPP and LPP may be similar. The present results suggest that luteal persistence during SPP and LPP may be due to delayed peak release of prostaglandin F2 alpha by the uterus.
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maternal recognition of pregnancy in swine i minimal requirement for exogenous estradiol 17 beta to induce either short or long Pseudopregnancy in cycling gilts
Biology of Reproduction, 1996Co-Authors: Anthony E Pusateri, Janet M Smith, James W Smith, Peter J Thomford, M A DiekmanAbstract:Five experiments were conducted to determine the minimal requirement for estradiol-171 (E 2) injections to induce either short Pseudopregnancy (SPP) or long Pseudopregnancy (LPP) in cycling gilts. In experiments 1 through 5, E 2 was injected i.m. on combinations of days between 11 and 25 days postestrus. Exogenous E 2 on Days 12 and 13 or on Days 12 through 19 was optimal for induction of SPP or LPP, respectively. The duration of E2-induced diestrus was clearly demarcated between SPP (n = 73, duration 23-35 days) and LPP (n = 23, duration > 50 days). A sixth experiment was conducted to determine the minimum dose of intrauterine E 2 required to induce SPP, and these gilts received intrauterine infusions of 0, 4, 40, or 400 tig E 2 per 24 h on Days 12 and 13 postestrus. Pseudopregnancy was induced in 0 of 12, 1 of 4, 1 of 11, and 4 of 7 gilts in the treatment groups, respectively. These data suggest that uterine exposure alone is not sufficient to induce SPP. The present results indicate that the optimal signal for inducing LPP in unmated cycling gilts, and perhaps also for maternal recognition of pregnancy in mated gilts, may occur in two phases with continuous exposure to E 2 being required from Day 12 to Days 17-19.
Anthony E Pusateri - One of the best experts on this subject based on the ideXlab platform.
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maternal recognition of pregnancy in swine ii plasma concentrations of progesterone and 13 14 dihydro 15 keto prostaglandin f2 alpha during the estrous cycle and during short and long Pseudopregnancy in gilts
Biology of Reproduction, 1996Co-Authors: Anthony E Pusateri, Matthew E Wilson, M A DiekmanAbstract:Two experiments were conducted to determine plasma progesterone (P4) and 13,14-dihydro-15-keto-prostaglandin F2 alpha (PGFM) concentrations in unmated gilts induced to have either short Pseudopregnancy (SPP) or long Pseudopregnancy (LPP). In experiment 1, estradiol-17 beta (E2) was injected on different combinations of days between Days 11 and 16 of the estrous cycle. For gilts induced to exhibit SPP, the interestrous interval averaged 27.0 +/- 0.4 days compared to the control interval of 20.0 +/- 0.4 days. In experiment 2, E2 injections were given on Days 12 and 13 or on Days 12 through 25. Interestrous intervals in SPP and nonpseudopregnant gilts were 25.6 +/- 0.2 and 19.9 +/- 0.6 days, respectively. Four of six gilts treated with E2 on Days 12-25 were induced to have LPP lasting more than 100 days. In both experiments, plasma P4 declined to baseline approximately 3 days before posttreatment estrus, regardless of type of Pseudopregnancy induced. Plasma PGFM peaked 4-6 days before posttreatment estrus in gilts displaying each type of response. In gilts exhibiting LPP, plasma PGFM concentrations tended to increase steadily during Pseudopregnancy. These data suggest that the mechanisms of luteolysis during the estrous cycle of unmated gilts and during estrogen-induced SPP and LPP may be similar. The present results suggest that luteal persistence during SPP and LPP may be due to delayed peak release of prostaglandin F2 alpha by the uterus.
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maternal recognition of pregnancy in swine i minimal requirement for exogenous estradiol 17 beta to induce either short or long Pseudopregnancy in cycling gilts
Biology of Reproduction, 1996Co-Authors: Anthony E Pusateri, Janet M Smith, James W Smith, Peter J Thomford, M A DiekmanAbstract:Five experiments were conducted to determine the minimal requirement for estradiol-171 (E 2) injections to induce either short Pseudopregnancy (SPP) or long Pseudopregnancy (LPP) in cycling gilts. In experiments 1 through 5, E 2 was injected i.m. on combinations of days between 11 and 25 days postestrus. Exogenous E 2 on Days 12 and 13 or on Days 12 through 19 was optimal for induction of SPP or LPP, respectively. The duration of E2-induced diestrus was clearly demarcated between SPP (n = 73, duration 23-35 days) and LPP (n = 23, duration > 50 days). A sixth experiment was conducted to determine the minimum dose of intrauterine E 2 required to induce SPP, and these gilts received intrauterine infusions of 0, 4, 40, or 400 tig E 2 per 24 h on Days 12 and 13 postestrus. Pseudopregnancy was induced in 0 of 12, 1 of 4, 1 of 11, and 4 of 7 gilts in the treatment groups, respectively. These data suggest that uterine exposure alone is not sufficient to induce SPP. The present results indicate that the optimal signal for inducing LPP in unmated cycling gilts, and perhaps also for maternal recognition of pregnancy in mated gilts, may occur in two phases with continuous exposure to E 2 being required from Day 12 to Days 17-19.
