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1.
Anim Reprod Sci ; 212: 106232, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31864498

RESUMO

Although combining of eCG and hCG administrations is known to enhance LH-like actions, there have been few studies where there was comparison of the effects of treatment of anestrous ewes with eCG and hCG and eCG alone. In Experiment 1, 18 ewes in seasonal anestrus were administered an intravaginal device (IVD) containing medroxyprogesterone acetate for 12 days, and at the time of IVD removal (D0), were allocated into the following groups (n = 6/group): no further treatment (control); 400 IU eCG (eCG); or 400 IU eCG and 200 IU hCG (eCG + hCG). There was greater ovarian follicular growth in the groups treated with gonadotropins, compared to the control, and there were greater progesterone concentrations in the eCG + hCG group on D9 (P < 0.05). In Experiment 2, 66 ewe lambs were assigned to the same treatment groups described for Experiment 1, and subsequently there was natural mating with rams. There was a greater rate of behavioral estrous manifestation in the eCG (88.5 %; 23/26) and eCG+hCG (85.2 %; 23/27), than control (30.8 %; 4/13; P < 0.05) group. Pregnancy rate was also greater in the eCG (34.6 %; 9/26) and eCG+hCG (18.6 %; 5/27) than control (0 %; 0/13; P < 0.05) group, whereas conception rate, considering only ewe lambs that were mated, was only greater in the eCG group. Although there were greater progesterone concentrations 9 days after treatment in the eCG+hCG group, there was no difference in follicular growth in anestrous ewes, nor was there an effect on estrous behavior manifestation and pregnancy rates in ewe lambs, compared to treatment with only eCG.

2.
Anim Reprod Sci ; 205: 150-155, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31076217

RESUMO

As oocytes and embryos of pigs have greater lipid content in the cytoplasm than those of other species, supplementation of the medium for in vitro maturation (IVM) of oocytes with omega-3 polyunsaturated fatty acids (PUFA) may help to improve embryo development. This study was conducted to evaluate effects of the inclusion of the docosaexaenoic (DHA) and of the eicosapentaenoic acids (EPA) in the IVM medium on the development of pig oocytes and on the lipid content of oocytes and embryos. In all experiments, control media consisted of porcine follicular fluid and oocytes were activated through parthenogenesis. In Experiment 1, there were four treatments for each PUFA: one control; and three treatments including EPA or DHA in the IVM medium at 12.5 µM, 25.0 µM and 50.0 µM). In Experiment 2, inclusion of 50 µM DHA was compared against the control. Cleavage rates in the IVM medium including 12.5 µM EPA and blastocyst development rates in media at any EPA concentration were less than for the control in Experiment 1 (P < 0.05). Compared to the control, inclusion of 50 µM DHA in the IVM medium was related to greater cleavage rates and greater number of embryo cells, in Experiment 1, and lesser lipid content in oocytes after 22 and 44 h and in embryos after 7 days, in Experiment 2 (both P < 0.05). Addition of DHA in the IVM medium may benefit the development of pig oocytes, but EPA appears to be cytotoxic.


Assuntos
Ácidos Docosa-Hexaenoicos/farmacologia , Ácido Eicosapentaenoico/farmacologia , Embrião de Mamíferos/química , Técnicas de Maturação in Vitro de Oócitos/veterinária , Oócitos/efeitos dos fármacos , Suínos/embriologia , Animais , Ácidos Docosa-Hexaenoicos/administração & dosagem , Relação Dose-Resposta a Droga , Ácido Eicosapentaenoico/administração & dosagem , Feminino , Metabolismo dos Lipídeos , Partenogênese , Suínos/fisiologia
3.
Reprod Domest Anim ; 53(3): 710-717, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29537121

RESUMO

Natriuretic peptides (NPs) are known to regulate reproductive events in polyovulatory species, but their function and regulation in monovulatory species remain to be fully characterized. Using a well-established in vivo model, we found that bovine granulosa cells from follicles near the deviation stage express mRNA for the three NP receptors (NPR1, NPR2 and NPR3), but not for NP precursors (NPPA, NPPB and NPPC). The abundance of NPR3 mRNA was higher in dominant compared to subordinate follicles at the expected time of follicular deviation. After deviation, mRNA for all NP receptors was significantly more abundant in the dominant follicle. Intrafollicular inhibition of oestrogen receptors downregulated NPR1 mRNA in dominant follicles. In granulosa cells from preovulatory follicles, NPPC mRNA increased at 3 and 6 h after systemic GnRH treatment, but decreased at 12 and 24 h to similar levels observed in samples collected at 0 h. After GnRH treatment, NPR1 mRNA was upregulated at 24 h, NPR3 mRNA gradually decreased after 3 h, while NPR2 mRNA was not regulated. The mRNA expression of the enzyme FURIN increased at 24 h after GnRH treatment. These findings revealed that the expression of mRNA encoding important components of the NP system is regulated in bovine granulosa cells during follicular deviation and in response to GnRH treatment, which suggests a role of NP system in the modulation of these processes in monovulatory species.


Assuntos
Bovinos/fisiologia , Peptídeos Natriuréticos/metabolismo , Folículo Ovariano/fisiologia , Animais , Feminino , Furina/genética , Furina/metabolismo , Regulação da Expressão Gênica , Hormônio Liberador de Gonadotropina/farmacologia , Células da Granulosa/metabolismo , Peptídeos Natriuréticos/genética , Ovulação/fisiologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores Estrogênicos
4.
Andrologia ; 50(3)2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29143963

RESUMO

The paraoxonases types 1, 2 and 3 (PON1, PON2 and PON3, respectively) are enzymes that degrade lipid peroxides, preventing oxidative damages relevant for male reproductive function. This study determined the expression of those three paraoxonases in reproductive tissues of bulls and evaluated correlations among the activity of PON1 in the serum and seminal plasma with breeding soundness parameters in bulls. The expression of PON1, PON2 and PON3 was characterised by RT-PCR in samples of testicular parenchyma, vesicular glands and epididymis collected from three slaughtered bulls. All three paraoxonases were expressed in the testicular parenchyma, PON2 and PON3 were both expressed in the epididymis head and PON3 was also expressed in the epididymis tail. The PON1 activity was determined in samples of serum and seminal plasma from 110 bulls submitted to breeding soundness evaluation. There was a strong correlation (r = .90) between the activity of the PON1 in both serum and seminal plasma (p < .0001). The PON1 activity in the seminal plasma was positively correlated with ejaculate's colour, sperm mass activity (p = .04), motility, vigour and viability (all p < .01). Thus, PON1 may be a potential marker for sperm motility and viability in bulls.


Assuntos
Arildialquilfosfatase/metabolismo , Epididimo/metabolismo , Sêmen/enzimologia , Testículo/metabolismo , Animais , Biomarcadores/metabolismo , Bovinos , Ejaculação/fisiologia , Masculino , Estresse Oxidativo/fisiologia , Motilidade Espermática/fisiologia
5.
Reprod Fertil Dev ; 29(2): 234-243, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26194863

RESUMO

There is evidence that regulation of follicle selection in cattle involves locally produced growth factors. In the present study, we investigated the expression of members of the fibroblast growth factor (FGF) 7 family during follicle deviation. The largest and second largest follicles were recovered during the second day of a synchronised follicle wave and the future dominant and future subordinate follicles were identified based on diameter and cytochrome P450, family 19, subfamily A, polypeptide 1 (CYP19A1) mRNA levels in granulosa cells. Theca cells of the future dominant follicle contained less mRNA encoding FGF7 and FGF10 compared with those from the future subordinate follicle 2.5 days after ovulation, before a significant difference between the diameters of the future dominant and future subordinate follicles could be observed, but FGF22 mRNA levels did not change. Levels of mRNA encoding FGF receptors FGFR1B and FGFR2B in theca and granulosa cells, respectively, were lower in the future dominant follicle compared with the future subordinate follicle. Addition of FGF10 to granulosa cells in vitro significantly decreased oestradiol secretion, as well as CYP19A1, FSH receptor (FSHR) and insulin-like growth factor 1 receptor (IGF1R) mRNA abundance, whereas FGF22 had no effect. We conclude that FGF10 and FGFR2B expression is increased in the future subordinate follicle before morphological deviation, which may contribute to follicle selection.


Assuntos
Fator 10 de Crescimento de Fibroblastos/metabolismo , Folículo Ovariano/metabolismo , Ovário/metabolismo , Ovulação/metabolismo , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/metabolismo , Animais , Bovinos , Feminino , Fator 10 de Crescimento de Fibroblastos/farmacologia , Hormônio Foliculoestimulante/metabolismo , Células da Granulosa/efeitos dos fármacos , Células da Granulosa/metabolismo , Folículo Ovariano/efeitos dos fármacos , Ovário/efeitos dos fármacos , Ovulação/efeitos dos fármacos , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/metabolismo , Receptores do FSH/metabolismo , Células Tecais/efeitos dos fármacos , Células Tecais/metabolismo
6.
Reprod Domest Anim ; 51(5): 766-73, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27545763

RESUMO

The LH surge induces functional and morphological changes in granulosa cells. Mechanistic target of rapamycin (mTOR) is an integrator of signalling pathways in multiple cell types. We hypothesized that mTOR kinase activity integrates and modulates molecular pathways induced by LH in granulosa cells during the preovulatory period. Cows were ovariectomized and granulosa cells collected at 0, 3, 6, 12 and 24 hr after GnRH injection. While RHEB mRNA levels increased at 3 and 6 hr, returning to basal levels by 12 hr after GnRH treatment, RHOA mRNA levels increased at 6 hr and remained high thereafter. Western blot analyses revealed increased S6K phosphorylation at 3 and 6 hr after GnRH injection. Similarly, mRNA levels of ERK1/2, STAR and EGR-1 were higher 3 hr after GnRH treatment. Rapamycin treatment inhibited mTOR activity and increased AKT activity, but did not alter ERK1/2 phosphorylation and EGR1 protein levels in cultured bovine granulosa cells. Rapamycin also inhibited LH-induced increase in EREG mRNA abundance in granulosa cells in vitro. However, intrafollicular injection of rapamycin did not suppress ovulation. These findings suggest that mTOR is involved in the control of EREG expression in cattle, which may be triggered by LH surge stimulating RHEB and S6K activity.


Assuntos
Regulação da Expressão Gênica/fisiologia , Células da Granulosa/fisiologia , Hormônio Luteinizante/fisiologia , Ovulação/fisiologia , Serina-Treonina Quinases TOR/metabolismo , Animais , Bovinos , Feminino , Proteínas Monoméricas de Ligação ao GTP/genética , Proteínas Monoméricas de Ligação ao GTP/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transdução de Sinais , Sirolimo/administração & dosagem , Sirolimo/farmacologia , Serina-Treonina Quinases TOR/genética
7.
Anim Reprod Sci ; 170: 178-83, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27237813

RESUMO

Polyunsaturated fatty acids may benefit reproductive performance of female swine. This study evaluated metabolic and reproductive parameters of prepubertal finishing gilts fed with fish oil as a natural source of omega-3 fatty acids (6.88g/d) (n=12) over a period of 45 d. Gilts in the control group were fed soybean oil (n=13). Body weight and backfat were determined at 15-d intervals. Serum levels of leptin, IGF-1, insulin, cholesterol and triglycerides were measured at the beginning (D0) and at the end of the period (D45). Immunolabeling intensity for leptin and its receptor (ObRb) was assessed in oocytes of preantral follicles. Gilts fed omega-3 presented slightly heavier uteri (P=0.09) than control gilts, but there was no effect on body weight and backfat (P>0.05). Cholesterol serum levels tended to be lower at D45 for omega-3 supplemented gilts than for controls (P=0.06). Triglycerides and IGF-1 serum levels were lower at D45 than at D0 for control gilts (P<0.05), but unaltered for supplemented gilts. Insulin levels were unaffected by supplementation (P>0.05), but were greater at D45 than at D0 in both treatments (P<0.05). Immunolabeling for leptin and ObRb in oocytes included in preantral follicles was more intense for supplemented gilts than for control gilts (P<0.05). Omega-3 supplementation was associated with reduced serum cholesterol level and more intense staining for leptin in oocytes of prepubertal gilts, which suggests some involvement on triggering puberty.


Assuntos
Ácidos Graxos Ômega-3/farmacologia , Maturidade Sexual/efeitos dos fármacos , Suínos/fisiologia , Animais , Suplementos Nutricionais , Ácidos Graxos Ômega-3/administração & dosagem , Feminino
8.
Reprod Domest Anim ; 51(2): 188-94, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26815645

RESUMO

The anti-Müllerian hormone (AMH) is an important marker of ovarian reserve and for predicting the response to superovulatory treatments in several species. The objective of this study was to investigate whether AMH and its receptor (AMHR2) are regulated in bovine granulosa cells during follicular development. In the first experiment, granulosa cells were retrieved from the two largest follicles on days 2 (before), 3 (at the expected time) or 4 (after deviation) of follicular wave. In the second experiment, four doses of FSH (30, 30, 20 and 20 mg) or saline were administered twice a day starting on Day 2 of the first follicular wave of the cycle. Granulosa cells and follicular fluid were collected from the two largest follicles 12 h after the last injection of FSH or saline. AMH mRNA abundance was similar in granulosa cells of the two largest follicles (F1 and F2) before deviation (Day 2), but greater in dominant (DF) than subordinate follicles (SF) at the expected time (Day 3) and after (Day 4) deviation (p < 0.05). In experiment 1, AMH mRNA levels declined in both DF and SF near the expected time and after deviation when compared to before deviation. There was no difference in AMHR2 mRNA levels before and during follicular deviation (p > 0.05), but they tended to be greater in DFs than SFs (p < 0.1) after deviation. Experiment 2 showed that AMH and AMHR2 mRNA in granulosa cells and AMH protein abundance in follicular fluid were similar (p > 0.05) between both co-dominant follicles collected from the FSH-treated cows. These findings indicate the followings: AMH mRNA levels decrease in both DFs and SFs during follicular deviation; granulosa cells from heathy follicles express more AMH mRNA compared to subordinate follicles undergoing atresia and FSH stimulates AMH and AMHR2 mRNA expression in granulosa cells of co-dominant follicles.


Assuntos
Hormônio Antimülleriano/metabolismo , Bovinos/fisiologia , Folículo Ovariano/fisiologia , Receptores de Peptídeos/metabolismo , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Animais , Hormônio Antimülleriano/genética , Feminino , Hormônio Foliculoestimulante/farmacologia , Atresia Folicular/genética , Atresia Folicular/fisiologia , Líquido Folicular/química , Líquido Folicular/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Células da Granulosa/efeitos dos fármacos , Células da Granulosa/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores de Peptídeos/genética , Receptores de Fatores de Crescimento Transformadores beta/genética
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