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Nava Dekel - One of the best experts on this subject based on the ideXlab platform.
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Cloprostenol a prostaglandin f2α analog induces hypoxia in rat placenta bold contrast mri
NMR in Biomedicine, 2007Co-Authors: Eliezer Girsh, Vicki Plaks, Assaf A Gilad, Nava Nevo, Edna Schechtman, Michal Neeman, Nava DekelAbstract:Blood oxygen level dependent (BOLD) contrast was used to monitor hypoxia induced by Cloprostenol, a prostaglandin F2α (PGF2α) analog, in the rat embryo-placental unit (EPU). It is shown that administration of Cloprostenol (0.025 mg/rat) at mid-gestation (day 16) reduced EPU oxygenation, as detected by BOLD contrast MRI, in correlation with induction of vascular endothelial growth factor (VEGF) gene (Vegfa) expression in the corresponding placenta (r = 0.56, p = 0.03). Elevated VEGF mRNA expression in response to Cloprostenol treatment was also observed at early gestation (day 9) in the forming placenta (p = 0.04) and uterus (p = 0.03). Cloprostenol increased the expression levels of endothelin-1 (ET-1) gene (Edn1) (p = 0.03) and its corresponding peptide (p = 0.02) in the forming placenta, as well as the expression of the endothelin receptor type A (ETA) gene (Ednra) in both the forming placenta (p = 0.009) and the uterus (p = 0.01). The levels of the endothelin receptor type B (ETB) gene (Ednrb) were not affected in response to Cloprostenol, but a significant elevation in the expression level of this receptor was observed in the uterus at mid- and late gestation (day 22) (p = 0.04 and 0.01 respectively), suggesting a role for ETB in the vasodilatory status of the pregnant uterus. It is suggested that PGF2α induces uteroplacental vasoconstriction in the rat, and that ET-1 may take part in mediating this effect, probably via activation of ETA receptor. The uteroplacental vasoconstriction induces hypoxia, as manifested by significant changes in BOLD MRI and by upregulation of VEGF. Copyright © 2006 John Wiley & Sons, Ltd.
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Involvement of endothelin‐1 and its receptors in PGF2α‐induced luteolysis in the rat
Molecular Reproduction and Development, 2002Co-Authors: Eliezer Girsh, Nava DekelAbstract:The possible mediatory role of endothelin-1 (ET-1) in prostaglandin F2α (PGF2α)-induced luteolysis in the rat was examined. The effect of PGF2α was tested on day 9 of pregnancy either in vivo, by injecting Cloprostenol, an analog of PGF2α or in vitro, in isolated intact corpora lutea incubated with PGF2α. Luteolysis was confirmed by progesterone determination in the peripheral blood serum or in the culture medium, respectively. Administration of Cloprostenol (.0025 mg/rat) induced within 1 hr, a significant fall (from 56.8 to 27.6 ng/ml, P
J R Pursley - One of the best experts on this subject based on the ideXlab platform.
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compared to dinoprost tromethamine Cloprostenol sodium increased rates of estrus detection conception and pregnancy in lactating dairy cows on a large commercial dairy
Theriogenology, 2012Co-Authors: J R Pursley, J P N Martins, C Wright, N D StewartAbstract:Abstract Using two PGF2α treatments 14 days apart as a way to enhance estrus detection rate following the 2nd treatment is a reproductive management tool that continues to be used on large dairy farms. In one study, in cows with a functional CL and a dominant follicle, treatment with Cloprostenol vs. dinoprost resulted in greater peripheral estradiol concentrations. The objective of the present study was to determine if Cloprostenol could enhance pregnancy rates of cows in a large dairy herd using a PGF2α program for 1st artificial insemination (AI). Lactating dairy cows (n = 4549) were randomly assigned to receive two treatments of either 500 μg Cloprostenol or 25 mg dinoprost 14 days apart, with the 2nd treatment on the 1st day of the voluntary waiting period (57 DIM). Cows detected in estrus within 5 days after the 2nd treatment were inseminated. There was no effect of treatment on day of estrus detection, with 78% of cows inseminated on Days 3 or 4 following treatment. Cloprostenol increased (P
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luteolytic effects of Cloprostenol sodium in lactating dairy cows treated with g6g ovsynch
Journal of Dairy Science, 2011Co-Authors: J P N Martins, R K Policelli, J R PursleyAbstract:Abstract The probability of a pregnancy decreases substantially in lactating dairy cows treated with Ovsynch if luteolysis is delayed or incomplete. Two PGF 2α products are currently approved in the United States for luteolysis in lactating dairy cattle, dinoprost tromethamine and Cloprostenol sodium. Cloprostenol has a longer half-life compared with dinoprost, is more resistant to endogenous metabolism, and is maintained in circulation longer. We hypothesized that Cloprostenol could reduce the time to complete luteolysis compared with dinoprost because of differences in half-life. Lactating dairy cows received the same presynchronization strategy (G6G; 25mg of PGF 2α – 2 d – 100μg of GnRH – 6 d – 100μg of GnRH – 7 d – final PGF 2α treatment). At the time of the final PGF 2α , cows (n=35) were randomly assigned to receive either 500μg of Cloprostenol or 25mg of dinoprost. Blood samples were collected daily before and serially after PGF 2α treatment to analyze circulating concentrations of progesterone (P 4 ) and estradiol (E 2 ). Ultrasound examinations of ovaries were performed to measure sizes of follicles and corpora lutea (CL) and determine time of ovulation. Considering only cows with complete luteolysis, mean circulating P 4 was lower for cows given Cloprostenol than for those given dinoprost between 0 and 12h postinjection, but not at 24, 36, or 48h. A rapid decrease in P 4 was observed 1h after PGF 2α (6.54±0.27 to 3.77±0.22ng/mL) followed by a complete rebound 1h later (3.77±0.22 to 5.07±0.31ng/mL) followed by a steady decline in both treatment groups. Serum concentrations of E 2 were greater at 48h posttreatment in Cloprostenol-treated cows (2.74±0.15pg/mL) than in dinoprost-treated cows (2.37±0.19pg/mL). Cows that did not have complete luteolysis did not ovulate (0/7) during the 6-d period following treatment. Time to complete luteolysis and ovulation was 29.1±1.1 versus 29.4±1.7 and 101 versus 103h posttreatment in Cloprostenol compared with dinoprost. A negative relationship was observed between P 4 at 12h posttreatment and concentrations of E 2 48h posttreatment (b=−0.6905; R 2 =0.23). In summary, cows treated with Cloprostenol had lower concentrations of P 4 for the first 12h following treatment and subsequently greater concentrations of E 2 compared with dinoprost, although no differences were observed in these 2 PGF 2α analogs for time to complete luteolysis or time to ovulation.
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Luteolytic effects of Cloprostenol sodium in lactating dairy cows treated with G6G/Ovsynch.
Journal of Dairy Science, 2011Co-Authors: J P N Martins, R K Policelli, J R PursleyAbstract:Abstract The probability of a pregnancy decreases substantially in lactating dairy cows treated with Ovsynch if luteolysis is delayed or incomplete. Two PGF 2α products are currently approved in the United States for luteolysis in lactating dairy cattle, dinoprost tromethamine and Cloprostenol sodium. Cloprostenol has a longer half-life compared with dinoprost, is more resistant to endogenous metabolism, and is maintained in circulation longer. We hypothesized that Cloprostenol could reduce the time to complete luteolysis compared with dinoprost because of differences in half-life. Lactating dairy cows received the same presynchronization strategy (G6G; 25mg of PGF 2α – 2 d – 100μg of GnRH – 6 d – 100μg of GnRH – 7 d – final PGF 2α treatment). At the time of the final PGF 2α , cows (n=35) were randomly assigned to receive either 500μg of Cloprostenol or 25mg of dinoprost. Blood samples were collected daily before and serially after PGF 2α treatment to analyze circulating concentrations of progesterone (P 4 ) and estradiol (E 2 ). Ultrasound examinations of ovaries were performed to measure sizes of follicles and corpora lutea (CL) and determine time of ovulation. Considering only cows with complete luteolysis, mean circulating P 4 was lower for cows given Cloprostenol than for those given dinoprost between 0 and 12h postinjection, but not at 24, 36, or 48h. A rapid decrease in P 4 was observed 1h after PGF 2α (6.54±0.27 to 3.77±0.22ng/mL) followed by a complete rebound 1h later (3.77±0.22 to 5.07±0.31ng/mL) followed by a steady decline in both treatment groups. Serum concentrations of E 2 were greater at 48h posttreatment in Cloprostenol-treated cows (2.74±0.15pg/mL) than in dinoprost-treated cows (2.37±0.19pg/mL). Cows that did not have complete luteolysis did not ovulate (0/7) during the 6-d period following treatment. Time to complete luteolysis and ovulation was 29.1±1.1 versus 29.4±1.7 and 101 versus 103h posttreatment in Cloprostenol compared with dinoprost. A negative relationship was observed between P 4 at 12h posttreatment and concentrations of E 2 48h posttreatment (b=−0.6905; R 2 =0.23). In summary, cows treated with Cloprostenol had lower concentrations of P 4 for the first 12h following treatment and subsequently greater concentrations of E 2 compared with dinoprost, although no differences were observed in these 2 PGF 2α analogs for time to complete luteolysis or time to ovulation.
Adrian Steiner - One of the best experts on this subject based on the ideXlab platform.
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effect of prostaglandin e2 dl Cloprostenol and prostaglandin e2 in combination with d Cloprostenol on uterine motility during diestrus in experimental cows
Animal Reproduction Science, 2003Co-Authors: Gabriela Hirsbrunner, U Kupfer, H Burkhardt, B Knutti, Adrian SteinerAbstract:Abstract Prostaglandin F2α is used in dairy herd management because of its luteolytic properties and for its direct effect on the myometrium in cows diagnosed with endometritis. Prostaglandin E2 has a contractile effect on the bovine uterus. In human medicine, prostaglandin E2 is routinely used to maintain labor and to ripen the cervix. We hypothesized, that a combination of prostaglandin F2α and prostaglandin E2 would provoke a long-lasting increase in intrauterine pressure (IUP) and uterine motility as compared to either prostaglandin group. Intrauterine pressure was recorded during the diestrus of eight lactating dairy cows using a transcervically placed intraluminal pressure microtransducer. After recording of physiologic uterine motility for 30 min, prostaglandins ( dl -Cloprostenol, PGE2, PGE2 in combination with d -Cloprostenol) or placebo were administered, followed by a 2 h recording period. Significant differences were found for the area under the curve, the mean amplitude and the intrauterine pressure, whereas the number of pressure waves did not differ significantly among treatments. Peak values for area under the curve and mean amplitude were found during the first 15 min for the combination of PGE2 and d -Cloprostenol. During the last 15 min of the recording session, area under the curve and mean amplitude were increased only for the combination of PGE2 and d -Cloprostenol as compared to placebo. Although PGF2α and PGE2 provoke an increase in intrauterine pressure, only their combination guarantees a significant effect over a 2 h recording period.
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effect of two dosages of d Cloprostenol on intrauterine pressure and uterine motility during dioestrus in experimental cows
Journal of Veterinary Medicine Series A-physiology Pathology Clinical Medicine, 1999Co-Authors: Gabriela Hirsbrunner, U Kupfer, H Burkhardt, B Knutti, Adrian SteinerAbstract:: Prostaglandins are commonly used in herd management for their luteolytic properties; however, prostaglandins also have a direct contractile effect on the myometrium. We hypothesized that different dosages (0.15 and 0.3 mg) of d-Cloprostenol, a synthetical prostaglandin F2 alpha preparation, would differ as to their contractile effects on the uterus. Intrauterine pressure was recorded during dioestrus of lactating dairy cows, using a transcervically placed intraluminal pressure microtransducer. After recording of physiological uterine motility for 30 min, a placebo or d-Cloprostenol at one of the two different dosages was administered intramuscularly, followed by a 2-h recording period. Significant differences were found for the area under the curve (P < or = 0.05) and mean amplitude (P < or = 0.05), whereas the number of spikes per 15 min and the baseline pressure during the last 3 min of every 15-min period did not differ significantly among treatments. Peak values for area under the curve and mean amplitude were found between 15 and 30 min after administration of the lower dosage of d-Cloprostenol, and between 75 and 90 min after administration of the higher dosage. Using the higher dosage of d-Cloprostenol, a steady plateau from 15 to 30 min after administration until the end of the recording session was obtained. Thus, double the luteolytic dose of the d-Cloprostenol preparation gives a significantly better reaction in terms of uterine contractility than the single dose.
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effect of different prostaglandins on intrauterine pressure and uterine motility during diestrus in experimental cows
Theriogenology, 1998Co-Authors: Gabriela Hirsbrunner, U Kupfer, H Burkhardt, Adrian SteinerAbstract:Abstract Prostaglandins are widely used in herd management due to their luteolytic properties. They have also a direct effect on the myometrium. We hypothesized, that dissimilar prostaglandin preparations would differ as to their contractile effect. Intrauterine pressure was recorded during the diestrus of lactating dairy cows using a transcervically placed intraluminal pressure microtransducer. After recording physiologic uterine motility for 30 min, prostaglandins (dinoprost, DL-Cloprostenol, DCloprostenol) or a placebo was administered intramuscularly, followed by a 2-h recording period. Significant differences were found for the area under the curve (P
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Effect of different prostaglandins on intrauterine pressure and uterine motility during diestrus in experimental cows.
Theriogenology, 1998Co-Authors: Gabriela Hirsbrunner, U Kupfer, H Burkhardt, Adrian SteinerAbstract:Prostaglandins are widely used in herd management due to their luteolytic properties. They have also a direct effect on the myometrium. We hypothesized, that dissimilar prostaglandin preparations would differ as to their contractile effect. Intrauterine pressure was recorded during the diestrus of lactating dairy cows using a transcervically placed intraluminal pressure microtransducer. After recording physiologic uterine motility for 30 min, prostaglandins (dinoprost, DL-Cloprostenol, D-Cloprostenol) or a placebo was administered intramuscularly, followed by a 2-h recording period. Significant differences were found for the area under the curve (P < or = 0.05) and mean amplitude (P < or = 0.05), whereas the number of spikes per 15 min and the baseline pressure during the last 3 min of every recording period did not differ significantly among treatments. Peak values for area under the curve and mean amplitude were found between 15 and 30 min after administration of DL-Cloprostenol, while dinoprost yielded the steadiest plateau from this period until the end of the recording session. These results contrast with those of earlier studies comparing prostaglandins after intravenous administration.
Eliezer Girsh - One of the best experts on this subject based on the ideXlab platform.
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Cloprostenol a prostaglandin f2α analog induces hypoxia in rat placenta bold contrast mri
NMR in Biomedicine, 2007Co-Authors: Eliezer Girsh, Vicki Plaks, Assaf A Gilad, Nava Nevo, Edna Schechtman, Michal Neeman, Nava DekelAbstract:Blood oxygen level dependent (BOLD) contrast was used to monitor hypoxia induced by Cloprostenol, a prostaglandin F2α (PGF2α) analog, in the rat embryo-placental unit (EPU). It is shown that administration of Cloprostenol (0.025 mg/rat) at mid-gestation (day 16) reduced EPU oxygenation, as detected by BOLD contrast MRI, in correlation with induction of vascular endothelial growth factor (VEGF) gene (Vegfa) expression in the corresponding placenta (r = 0.56, p = 0.03). Elevated VEGF mRNA expression in response to Cloprostenol treatment was also observed at early gestation (day 9) in the forming placenta (p = 0.04) and uterus (p = 0.03). Cloprostenol increased the expression levels of endothelin-1 (ET-1) gene (Edn1) (p = 0.03) and its corresponding peptide (p = 0.02) in the forming placenta, as well as the expression of the endothelin receptor type A (ETA) gene (Ednra) in both the forming placenta (p = 0.009) and the uterus (p = 0.01). The levels of the endothelin receptor type B (ETB) gene (Ednrb) were not affected in response to Cloprostenol, but a significant elevation in the expression level of this receptor was observed in the uterus at mid- and late gestation (day 22) (p = 0.04 and 0.01 respectively), suggesting a role for ETB in the vasodilatory status of the pregnant uterus. It is suggested that PGF2α induces uteroplacental vasoconstriction in the rat, and that ET-1 may take part in mediating this effect, probably via activation of ETA receptor. The uteroplacental vasoconstriction induces hypoxia, as manifested by significant changes in BOLD MRI and by upregulation of VEGF. Copyright © 2006 John Wiley & Sons, Ltd.
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Involvement of endothelin‐1 and its receptors in PGF2α‐induced luteolysis in the rat
Molecular Reproduction and Development, 2002Co-Authors: Eliezer Girsh, Nava DekelAbstract:The possible mediatory role of endothelin-1 (ET-1) in prostaglandin F2α (PGF2α)-induced luteolysis in the rat was examined. The effect of PGF2α was tested on day 9 of pregnancy either in vivo, by injecting Cloprostenol, an analog of PGF2α or in vitro, in isolated intact corpora lutea incubated with PGF2α. Luteolysis was confirmed by progesterone determination in the peripheral blood serum or in the culture medium, respectively. Administration of Cloprostenol (.0025 mg/rat) induced within 1 hr, a significant fall (from 56.8 to 27.6 ng/ml, P
J P N Martins - One of the best experts on this subject based on the ideXlab platform.
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compared to dinoprost tromethamine Cloprostenol sodium increased rates of estrus detection conception and pregnancy in lactating dairy cows on a large commercial dairy
Theriogenology, 2012Co-Authors: J R Pursley, J P N Martins, C Wright, N D StewartAbstract:Abstract Using two PGF2α treatments 14 days apart as a way to enhance estrus detection rate following the 2nd treatment is a reproductive management tool that continues to be used on large dairy farms. In one study, in cows with a functional CL and a dominant follicle, treatment with Cloprostenol vs. dinoprost resulted in greater peripheral estradiol concentrations. The objective of the present study was to determine if Cloprostenol could enhance pregnancy rates of cows in a large dairy herd using a PGF2α program for 1st artificial insemination (AI). Lactating dairy cows (n = 4549) were randomly assigned to receive two treatments of either 500 μg Cloprostenol or 25 mg dinoprost 14 days apart, with the 2nd treatment on the 1st day of the voluntary waiting period (57 DIM). Cows detected in estrus within 5 days after the 2nd treatment were inseminated. There was no effect of treatment on day of estrus detection, with 78% of cows inseminated on Days 3 or 4 following treatment. Cloprostenol increased (P
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luteolytic effects of Cloprostenol sodium in lactating dairy cows treated with g6g ovsynch
Journal of Dairy Science, 2011Co-Authors: J P N Martins, R K Policelli, J R PursleyAbstract:Abstract The probability of a pregnancy decreases substantially in lactating dairy cows treated with Ovsynch if luteolysis is delayed or incomplete. Two PGF 2α products are currently approved in the United States for luteolysis in lactating dairy cattle, dinoprost tromethamine and Cloprostenol sodium. Cloprostenol has a longer half-life compared with dinoprost, is more resistant to endogenous metabolism, and is maintained in circulation longer. We hypothesized that Cloprostenol could reduce the time to complete luteolysis compared with dinoprost because of differences in half-life. Lactating dairy cows received the same presynchronization strategy (G6G; 25mg of PGF 2α – 2 d – 100μg of GnRH – 6 d – 100μg of GnRH – 7 d – final PGF 2α treatment). At the time of the final PGF 2α , cows (n=35) were randomly assigned to receive either 500μg of Cloprostenol or 25mg of dinoprost. Blood samples were collected daily before and serially after PGF 2α treatment to analyze circulating concentrations of progesterone (P 4 ) and estradiol (E 2 ). Ultrasound examinations of ovaries were performed to measure sizes of follicles and corpora lutea (CL) and determine time of ovulation. Considering only cows with complete luteolysis, mean circulating P 4 was lower for cows given Cloprostenol than for those given dinoprost between 0 and 12h postinjection, but not at 24, 36, or 48h. A rapid decrease in P 4 was observed 1h after PGF 2α (6.54±0.27 to 3.77±0.22ng/mL) followed by a complete rebound 1h later (3.77±0.22 to 5.07±0.31ng/mL) followed by a steady decline in both treatment groups. Serum concentrations of E 2 were greater at 48h posttreatment in Cloprostenol-treated cows (2.74±0.15pg/mL) than in dinoprost-treated cows (2.37±0.19pg/mL). Cows that did not have complete luteolysis did not ovulate (0/7) during the 6-d period following treatment. Time to complete luteolysis and ovulation was 29.1±1.1 versus 29.4±1.7 and 101 versus 103h posttreatment in Cloprostenol compared with dinoprost. A negative relationship was observed between P 4 at 12h posttreatment and concentrations of E 2 48h posttreatment (b=−0.6905; R 2 =0.23). In summary, cows treated with Cloprostenol had lower concentrations of P 4 for the first 12h following treatment and subsequently greater concentrations of E 2 compared with dinoprost, although no differences were observed in these 2 PGF 2α analogs for time to complete luteolysis or time to ovulation.
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Luteolytic effects of Cloprostenol sodium in lactating dairy cows treated with G6G/Ovsynch.
Journal of Dairy Science, 2011Co-Authors: J P N Martins, R K Policelli, J R PursleyAbstract:Abstract The probability of a pregnancy decreases substantially in lactating dairy cows treated with Ovsynch if luteolysis is delayed or incomplete. Two PGF 2α products are currently approved in the United States for luteolysis in lactating dairy cattle, dinoprost tromethamine and Cloprostenol sodium. Cloprostenol has a longer half-life compared with dinoprost, is more resistant to endogenous metabolism, and is maintained in circulation longer. We hypothesized that Cloprostenol could reduce the time to complete luteolysis compared with dinoprost because of differences in half-life. Lactating dairy cows received the same presynchronization strategy (G6G; 25mg of PGF 2α – 2 d – 100μg of GnRH – 6 d – 100μg of GnRH – 7 d – final PGF 2α treatment). At the time of the final PGF 2α , cows (n=35) were randomly assigned to receive either 500μg of Cloprostenol or 25mg of dinoprost. Blood samples were collected daily before and serially after PGF 2α treatment to analyze circulating concentrations of progesterone (P 4 ) and estradiol (E 2 ). Ultrasound examinations of ovaries were performed to measure sizes of follicles and corpora lutea (CL) and determine time of ovulation. Considering only cows with complete luteolysis, mean circulating P 4 was lower for cows given Cloprostenol than for those given dinoprost between 0 and 12h postinjection, but not at 24, 36, or 48h. A rapid decrease in P 4 was observed 1h after PGF 2α (6.54±0.27 to 3.77±0.22ng/mL) followed by a complete rebound 1h later (3.77±0.22 to 5.07±0.31ng/mL) followed by a steady decline in both treatment groups. Serum concentrations of E 2 were greater at 48h posttreatment in Cloprostenol-treated cows (2.74±0.15pg/mL) than in dinoprost-treated cows (2.37±0.19pg/mL). Cows that did not have complete luteolysis did not ovulate (0/7) during the 6-d period following treatment. Time to complete luteolysis and ovulation was 29.1±1.1 versus 29.4±1.7 and 101 versus 103h posttreatment in Cloprostenol compared with dinoprost. A negative relationship was observed between P 4 at 12h posttreatment and concentrations of E 2 48h posttreatment (b=−0.6905; R 2 =0.23). In summary, cows treated with Cloprostenol had lower concentrations of P 4 for the first 12h following treatment and subsequently greater concentrations of E 2 compared with dinoprost, although no differences were observed in these 2 PGF 2α analogs for time to complete luteolysis or time to ovulation.