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1.
J Assist Reprod Genet ; 31(8): 1003-12, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24928054

RESUMO

PURPOSE: To evaluate the effect of cryopreservation and thawing of ovarian tissue from oncological patients opting for fertility preservation on ovarian tissue viability. METHODS: In this prospective cohort study, the ovarian tissue viability before and after cryopreservation and thawing was measured for 25 newly diagnosed oncological patients who had their ovarian tissue cryopreserved. Outcome measures were follicle integrity (histology), follicle viability (Calcein viability assay), steroid hormone production (estradiol and progesterone production in vitro) and overall tissue viability (glucose uptake in vitro). This study was conducted at a Cryobank for storage of ovarian tissue in a university hospital. RESULTS: Cryopreserved/thawed ovarian tissue showed a decreased glucose uptake when compared to tissue that had not been cryopreserved. In addition, a diminished E2 and P4 production was observed after cryopreservation and thawing, despite the fact that numbers of viable follicles as determined by the Calcein viability assay were comparable. Histological examination revealed a higher percentage of degenerated follicles after cryopreservation and thawing. CONCLUSIONS: Ovarian tissue cryopreservation and thawing impairs the viability of ovarian tissue in oncological patients opting for fertility preservation.


Assuntos
Criopreservação , Oócitos/citologia , Folículo Ovariano/citologia , Ovário/citologia , Preservação de Tecido , Adolescente , Adulto , Crioprotetores/farmacologia , Europa (Continente) , Feminino , Preservação da Fertilidade , Humanos , Oócitos/efeitos dos fármacos , Folículo Ovariano/efeitos dos fármacos , Ovário/efeitos dos fármacos , Estudos Prospectivos , Sobrevivência de Tecidos , Adulto Jovem
2.
Reprod Fertil Dev ; 23(8): 1034-42, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22127008

RESUMO

Oocyte secreted factors (OSFs) have emerged as important factors for follicular development. The present study investigated the effect of the potential OSF bone morphogenic protein (BMP)-6 on steroidogenesis in porcine cumulus oocyte complexes during in vitro maturation. Cumulus oocyte complexes (COCs), cumulus complexes (CCs) without oocytes and CCs with supplemented BMP-6 were cultured for 0, 5, 26 or 46 h. BMP-6 transcripts were detected in oocytes and cumulus cells at all time points. In both cell types the mRNA expression was most intense after 5h, and decreased during further maturation. After 26 and 46 h of culture, CCs secreted significantly less 17ß-estradiol than COCs. This effect was reversed by adding BMP-6 to CCs cultures. In addition, a down-regulation of Cyp19A1, the rate-limiting enzyme of 17ß-estradiol synthesis, was detected in CC cultures after 5h. As seen for 17ß-estradiol secretion, the addition of BMP-6 caused a significant increase in Cyp19A1 mRNA levels after 5, 26 and 46 h of culture. Progesterone secretion and transcripts of steroidogenic marker proteins StAR and 3ß-HSD were not affected considerably by oocyte removal or addition of BMP-6. Furthermore, BMP-6 did not affect the activity of the mitogen-activated protein kinase. The results indicated that BMP-6 is a potential OSF and is involved in the prevention of premature luteinisation in cumulus cells via enhancing 17ß-estradiol synthesis.


Assuntos
Proteína Morfogenética Óssea 6/metabolismo , Proteína Morfogenética Óssea 6/farmacologia , Células do Cúmulo/efeitos dos fármacos , Células do Cúmulo/metabolismo , Oócitos/efeitos dos fármacos , Oócitos/metabolismo , RNA Mensageiro/metabolismo , Esteroides/metabolismo , Animais , Aromatase/metabolismo , Células Cultivadas , Células do Cúmulo/citologia , Estradiol/metabolismo , Feminino , Técnicas In Vitro , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Modelos Animais , Oócitos/citologia , Fosforilação , Progesterona/metabolismo , Transdução de Sinais , Suínos
3.
Reprod Domest Anim ; 46(3): 513-9, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20946537

RESUMO

The aim of this study was to investigate steroidogenesis within porcine cumulus oocyte complexes during in vitro maturation and to examine the possible influence of the mitogen-activated protein kinase (MAPK). Porcine cumulus oocyte complexes were matured in vitro with and without the MAPK kinase inhibitor U0126 for 0, 5, 26 and 46 h. The 17ß-estradiol and progesterone concentration in the culture medium were then determined. In addition, the mRNA levels of StAR, Cyp11A1, 3ß-HSD and Cyp19A1 in cumulus cells were analysed by RT-PCR. Using an immunoblot, the MAPK phosphorylation in cumulus cells and oocytes was examined. During the first 26 h of in vitro maturation, 17ß-estradiol secretion was predominant, whereas, after a culture period of 46 h, the progesterone secretion decreased conspicuously. Under the influence of U0126, the secretion of 17ß-estradiol increased progressively during the complete maturation period, while progesterone secretion was completely inhibited. The mRNA levels of StAR and Cyp11A1 were not altered by U0126; however, corresponding to the hormone secretion, the gene expression of Cyp19A1 was up-regulated and the expression of 3ß-HSD down-regulated. The results suggested an influence of the MAPK on steroidogenesis in cumulus cells comparable to a luteinization factor. Hormone synthesis in cumulus cells during oocyte maturation seems to be regulated by altering expression of Cyp19A1 and 3ß-HSD.


Assuntos
Células do Cúmulo/metabolismo , Estradiol/biossíntese , Proteínas Quinases Ativadas por Mitógeno/fisiologia , Oócitos/metabolismo , Progesterona/biossíntese , Sus scrofa/metabolismo , 3-Hidroxiesteroide Desidrogenases/genética , Animais , Aromatase/genética , Butadienos/farmacologia , Células Cultivadas , Células do Cúmulo/enzimologia , Feminino , Regulação Enzimológica da Expressão Gênica , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , Nitrilas/farmacologia , Oócitos/crescimento & desenvolvimento , Fosforilação , RNA Mensageiro/análise , Suínos , Fatores de Tempo
4.
Reprod Domest Anim ; 45(6): e398-404, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20210885

RESUMO

The role of mitogen-activated protein kinase (MAPK) was investigated during ageing of porcine oocytes following in vitro maturation (IVM). Oocytes exhibiting an extruded first polar body after IVM for 46 h (79.3% metaphase II, M II) were used for the experiments. Nuclear maturation stages were not visibly altered after a further 12 h of ageing. Proportion of M II stages (42.9%) decreased significantly whereas fragmentation and degeneration of oocytes increased after an ageing time of 26 h. In vitro ageing for 12 and 26 h led to a significant reduction of MAPK phosphorylation (i.e. activation) compared to oocytes matured for 46 h. When MAPK was inhibited by U0126 in M II oocytes, 30.9% (12 h) and 39.7% (26 h) of oocytes, respectively, left metaphase II arrest and proceeded to early anaphase II. Pronuclear stages or fragmentation could be observed only sporadically (2.6-3.6%). After parthenogenetic activation of oocytes by ethanol/cycloheximide, cleavage stages were reached with rates of 51.9% (46 h IVM), 42.0% (12 h ageing) and 40.3% (26 h ageing), respectively. Furthermore, a significant higher proportion of long-term aged oocytes (26 h) showed pronuclear formation (8.6%) and fragmentation (7.9%) compared to non-aged oocytes (each 1.9%). It is concluded that both MAPK phosphorylation and cleavage rate after parthenogenetic activation decreased before alterations of nuclear stages could be detected during in vitro ageing of M II oocytes. A premature MAPK dephosphorylation of M II oocytes caused early anaphase II stages, but cleaved stages could not be achieved.


Assuntos
Meiose/fisiologia , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Oócitos/fisiologia , Partenogênese/fisiologia , Fosforilação/fisiologia , Suínos/fisiologia , Animais , Butadienos/farmacologia , Núcleo Celular , MAP Quinase Quinase Quinases/antagonistas & inibidores , Nitrilas/farmacologia , Oócitos/citologia
5.
Reprod Domest Anim ; 44(2): 235-40, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19323796

RESUMO

Effects of different media (TCM 199 + BSA, TCM 199 + FCS, TCM 199 + NBCS, Whitten's medium + BSA) supplemented with estradiol-17beta and two isolated and everted follicle shells on MPF and MAP kinase activities and the sensitivity to parthenogenetic activation of pig oocytes were examined at the end of culture (48 h). Elevated (P < 0.05) activities of MAP kinase were recorded in metaphase II oocytes following culture in Whitten's medium, whereas MPF levels were lowest (P < 0.05) in MII oocytes matured in TCM 199 supplemented with BSA. Oocytes matured in TCM 199 based media showed higher (P < 0.05) activation rates when compared to oocytes incubated in Whitten's medium. Whitten's medium supplemented with different protein sources (amino acids, FCS, BSA) was used to study the effects of different exposure periods to eCG/hCG stimulation on MPF and MAP kinase activities and in vivo fertilisability following culture for 48 h. MPF and MAP kinase activities were significantly increased by eCG/hCG stimulation of COCs during maturation. Further, the continuous presence of eCG/hCG during culture (48 h) significantly increased the levels of both kinases in comparison to stimulation by gonadotrophins alone during the first 24 h of incubation. In vivo fertilisation of oocytes matured in Whitten's medium supplemented with eCG/hCG for 24 or 48 h led to a significant retardation of early embryonic development compared to ovulated oocytes. In conclusion, media composition and gonadotrophin stimulation affect MPF/MAP kinase activities and the susceptibility to parthenogenetic activation of IVM oocytes. However, elevated kinase levels in pig oocytes following culture do not indicate complete cytoplasmic maturation.


Assuntos
Citoplasma/fisiologia , Histonas/análise , Proteínas Quinases Ativadas por Mitógeno/análise , Oócitos/química , Oócitos/enzimologia , Suínos , Animais , Núcleo Celular/fisiologia , Células Cultivadas , Gonadotropina Coriônica/farmacologia , Fase de Clivagem do Zigoto , Meios de Cultura , Feminino , Fertilização in vitro/veterinária , Metáfase , Oócitos/crescimento & desenvolvimento
6.
Dtsch Tierarztl Wochenschr ; 113(7): 251-5, 2006 Jul.
Artigo em Alemão | MEDLINE | ID: mdl-16892703

RESUMO

The objective of this study was to characterize the effect of an experimental infection with the classical swine fever (CSF) virus on libido and ejaculate parameters of adult boars. Four boars 10 month old were infected with a CSF field isolate (Visbek/Han95). Semen was collected every second day after infection and daily during the pyrexic phase. The only clinical signs in the boars were an increase in body temperature, but never above 39.9 degrees C and a temporally reduction of food intake. The libido was always good, so semen collection was performed in three boars without difficulty and the semen quality was always in the range of the minimum requirements for sperm that is used for artificial insemination. Although one boar had a good libido only a sperm free ejaculate could be collected on one day. The results show that a CSF virus infection of adult boars hardly causes any clinical symptoms and that sperm can be obtained despite fever. Insemination boars may thus be of special epidemiological relevance for the dissemination of the CSF virus.


Assuntos
Peste Suína Clássica/fisiopatologia , Ejaculação/fisiologia , Libido/fisiologia , Animais , Temperatura Corporal , Peste Suína Clássica/transmissão , Peste Suína Clássica/virologia , Masculino , Sêmen/química , Suínos , Fatores de Tempo
7.
Placenta ; 24(1): 107-12, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12495666

RESUMO

Molar transformations of the bovine placenta are extremly rare phenomenona and the aetiology of this genuine placental disease is still unknown. In the present study, an uncommon case of a German Holstein Friesian foetus co-twinned with a hydatidiform mole is described. Cytogenetic and fluorescence in situ hybridization analysis of cell cultures as well as prove of the presence of the SRY gene sequence revealed a heterosexual twin pregnancy. A chimeric condition of the mole was also established. In addition, an XO cell population was detected in the co-twin as well as in the mole. Upon examination of microsatellites of the parents, the mole and the co-twin an androgenetic origin of the mole is suggested, supporting the hypothesis that molar transformation of the bovine placenta may be caused by an androgenetic origin. Furthermore, the present observation demonstrates that the freemartin condition in cattle can be induced even in cases where severe placental transformations had subsequently occurred and no foetus proper could be detected at delivery.


Assuntos
Quimera , Freemartinismo/patologia , Mola Hidatiforme/veterinária , Neoplasias Uterinas/veterinária , Animais , Bovinos , Quimera/genética , DNA de Neoplasias/análise , Feminino , Freemartinismo/complicações , Freemartinismo/genética , Genótipo , Mola Hidatiforme/complicações , Mola Hidatiforme/genética , Mola Hidatiforme/patologia , Hibridização in Situ Fluorescente/veterinária , Masculino , Repetições de Microssatélites , Reação em Cadeia da Polimerase/veterinária , Gravidez , Processos de Determinação Sexual , Neoplasias Uterinas/complicações , Neoplasias Uterinas/genética , Neoplasias Uterinas/patologia , Cromossomo X , Cromossomo Y
8.
Obstet Gynecol ; 79(4): 523-8, 1992 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1532445

RESUMO

Healthy postmenopausal women were randomly assigned to groups receiving 28-day treatment cycles of estradiol (E2) valerate (2 mg, days 1-21) combined with medroxyprogesterone acetate (10 mg, days 12-21) (N = 18), 17 beta-estradiol (1.5 mg, days 1-24) combined with desogestrel (150 micrograms, days 13-24) (N = 20), or placebo (N = 18). The progestational effects on the endometrium were assessed by histology, uterine bleeding pattern, and biochemical markers of secretion measured in endometrial tissue (E2 and isocitrate dehydrogenase) and serum (placental protein 14). After 2 years of therapy, 24 women in the hormone groups had secretory endometrium and 13 had atrophic endometrium; in the placebo group, the results were one and 15, respectively. Withdrawal bleeding generally started between days 9-12 after the addition of progestogen in the E2-medroxyprogesterone acetate group, and between days 14-17 in the E2-desogestrel group. All three biochemical markers of secretion were increased in each of the hormone-treated groups compared with the placebo group (P less than .01-.001). Serum placental protein 14 was twice as high in the secretory as in the atrophic phase (P less than .01). Isocitrate dehydrogenase, but not E2 dehydrogenase, was also higher in the secretory phase (P less than .05). Only serum placental protein 14 was significantly related to the uterine bleeding pattern (P less than .01). We conclude that serum placental protein 14 reflects both endometrial histology and bleeding pattern and may be a useful marker of progestational effects on the endometrium. The markers of secretion measured in endometrial tissue are not as reliable for endometrial histology or bleeding pattern.


Assuntos
Endométrio/efeitos dos fármacos , Terapia de Reposição de Estrogênios , Glicoproteínas , Congêneres da Progesterona/uso terapêutico , Desogestrel , Estradiol/análogos & derivados , Estradiol/uso terapêutico , Estradiol Desidrogenases/metabolismo , Feminino , Glicodelina , Humanos , Isocitrato Desidrogenase/metabolismo , Medroxiprogesterona/análogos & derivados , Medroxiprogesterona/uso terapêutico , Acetato de Medroxiprogesterona , Pessoa de Meia-Idade , Norpregnenos/uso terapêutico , Proteínas da Gravidez/sangue , Hemorragia Uterina/induzido quimicamente
9.
Anim Reprod Sci ; 66(3-4): 175-84, 2001 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-11348780

RESUMO

The kinetics of nuclear maturation, M-phase promoting factor (MPF) and mitogen-activated protein kinase (MAP kinase) activities during in vitro maturation of porcine and bovine oocytes were examined. A further objective was to determine the duration of the meiotic stages during the maturation process. Porcine and bovine cumulus-oocyte complexes (COCs) were incubated in TCM 199 supplemented with 20% (v/v) heat inactivated fetal calf serum (FCS), 0.05microg/ml gentamycin, 0.02mg/ml insulin, 2.5microg/ml FSH and 5microg/ml LH. COCs were removed from the culture media in hourly intervals starting immediately after recovery from the follicle until 24 (bovine) or 48h (porcine) of culture. Oocytes were either fixed to evaluate the maturation status or the activity of MPF, assessed by its histone H1 kinase activity, and MAP kinase were determined by a radioactive assay simultaneously. In oocytes of both species, the MPF activity oscillated during the culture period with two maxima corresponding with the two metaphases: between 27-32 and after 46h (porcine) and between 6-9 and after 22h (bovine). There was a temporary decline in activity after 33-38 (porcine) and after 19h (bovine), which corresponded with anaphase I and telophase I. MAP kinase activity increased during the whole culture period and reached maximum levels after 47 (porcine) and after 22h (bovine). In porcine oocytes, the MAP kinase was activated before GVBD and MPF activation. In bovine oocytes, MPF and MAP kinase were activated at approximately the same time as the GVBD (8-9h of incubation). In average porcine, oocytes remain 23.4h in the germinal vesicle (GV) stage (13h in GV I, 5.7h in GV II, 3.2h in GV III and 1.5h in GV IV), 0.9h in diakinese, 9.6h in the metaphase I, 2.8h in anaphase I and 1.9h in telophase I of the first meiotic division. In bovine oocytes, the temporal distribution of the meiotic stages were 8.5h for the GV stage, 1.2h for diakinese, 8.3h for metaphase I, 1.6h for anaphase I and 1.9h for telophase I. These results indicate that the duration of the meiotic stages differs between the species and that MAP kinase is activated before MPF and GVBD in porcine oocytes.


Assuntos
Fator Promotor de Maturação/metabolismo , Meiose , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Oócitos/fisiologia , Animais , Bovinos , Núcleo Celular/fisiologia , Células Cultivadas , Meios de Cultura , Ativação Enzimática , Feminino , Cinética , Folículo Ovariano/citologia , Especificidade da Espécie
10.
Theriogenology ; 11(5): 351-65, 1979 May.
Artigo em Inglês | MEDLINE | ID: mdl-16725420

RESUMO

Effects of gonadotropins on the maturation of isolated oocytes and production of progesterone by porcine ovarian follicles from gonadotropin treated gilts have been studied in vitro. The addition of gonadotropins (2 I. U./ml, PMSG, HGC or 2 mg/ml FSH) to the culture medium resulted in increasing the number (84 - 90 %) of isolated oocytes which reached metaphase II. Expansion of the whole cumulus mass was observed only in media containing PMSG, whereas FSH or HCG alone did not cause these marked changes in the cumulus cells. Denudation of the eggs prior to culture gave no significant differences in the maturation rates between oocytes cultured in media with or without gonadotropins. In vitro maturation of follicle-enclosed oocytes took place only in HCG treated animals. Removing the ovary at 15 or 60 minutes after intravenous HCG administration induced oocyte maturation only in 22% and 17% respectively. A sharp increase in the number of oocytes which resume meiosis during follicle culture was observed 4 hours after HCG injection (84 %) and all of the oocytes of the gilts ovariectomized at 8 hours after HCG injection matured during the culture period. The progesterone production of isolated follicles from control gilts (only PMSG injected) increased slowly during a 96-hour culture period (from 48 to 240 ng progesterone/follicle), whereas the secretion of progesterone was drastically increased after a 15 minute interval between HCG injection and ovariectomy (from 42 to 950 ng progesterone/follicle). Follicles removed 24 hours after HCG injection showed a further increase in steroid production (2000 ng progesterone/follicle) and consistently secreted large amounts of progesterone during the culture period.

11.
Theriogenology ; 55(4): 847-65, 2001 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-11291909

RESUMO

Ewes are commonly superovulated with a single dose of eCG or multiple doses of pFSH. It would be convenient and less expensive to use a single dose of FSH, but results of various trials have been controversial. We wished to investigate ovarian dynamics using ultrasonography after superovulation with a single dose of pFSH and hMG as compared with a single dose of eCG. Estrus was synchronized during the breeding season with fluorogestone acetate-containing intravaginal sponges in adult German Merino ewes (n = 38). They were superovulated with single doses of pFSH (17 mg; n = 10), hMG (600 IU FSH and 600 IU LH; n = 9) or eCG (1250 IU; n = 10) given at the time of sponge removal, or pFSH (17 mg; n = 9) given 36h before sponge removal. Follicular and luteal development were observed by ultrasonic scanning every 8 h from the gonadotrophin injection until the end of estrus, and then once daily until Day 6 after estrus. Jugular venous blood was collected starting immediately before and 1 h after superovulation treatment, then twice daily until the end of estrus and once daily for the following 7 days. Concentrations of estradiol-17beta (E2) and progesterone (P4) were measured in plasma. Differences in the follicular dynamics of the 4 superovulation groups were obvious. The functional duration of the pFSH action was estimated to last approximately 48 h, whereas eCG and hMG were active for up to 72 h. The diameter of the ovulatory follicles proved to be smaller than it was described for unstimulated ewes. Single applications of pFSH or hMG can induce a superovulatory response, although the post-estrus progesterone profile revealed a high premature luteal regression rate in the different superovulation groups. Premature corpus luteum regression could not be seen by ultrasonography at this early stage of the luteal phase, indicating that the technique may fail to detect these corpora lutea in an embryo transfer program. However, ultrasonography represents a suitable method to observe follicular dynamics following different superovulation regimens in sheep.


Assuntos
Folículo Ovariano/diagnóstico por imagem , Ovinos/fisiologia , Superovulação , Administração Intravaginal , Animais , Gonadotropina Coriônica/administração & dosagem , Corpo Lúteo/diagnóstico por imagem , Estradiol/sangue , Estro/fisiologia , Sincronização do Estro , Feminino , Acetato de Fluorogestona/administração & dosagem , Hormônio Foliculoestimulante/administração & dosagem , Veias Jugulares , Cinética , Luteólise , Menotropinas/administração & dosagem , Progesterona/sangue , Ultrassonografia
12.
BMJ ; 315(7114): 989-91, 1997 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-9365296

RESUMO

OBJECTIVE: To investigate the prevalence of carcinoma in situ of the testis in a group of oligozoospermic men from infertile couples. DESIGN: A consecutive group of oligozoospermic men from infertile couples were offered bilateral testicular biopsy. The observed prevalence of carcinoma in situ was compared with the expected prevalence of testicular cancer in a corresponding age matched population of Danish men, assuming all untreated cases of carcinoma in situ progress to tumour stage. This calculation was based on data from the Danish Cancer Registry. SUBJECTS: 207 men aged 18-50 years who had sperm density below 10 million/ml in two samples within the previous 2 years or sperm density below 20 million/ml in two samples within the previous 2 years and a history of cryptorchidism or one or two atrophic testicles (orchidometer volume less than 15 cm3), or both. INTERVENTIONS: Bilateral testicular biopsies. MAIN OUTCOME MEASURES: Carcinoma in situ in the biopsy specimen. RESULTS: No case of carcinoma in situ was found among the 207 men. The expected number in a normal age matched population of corresponding size was 0.8. CONCLUSIONS: There is no increase in risk of carcinoma in situ of the testis in moderately oligozoospermic men of couples referred because of infertility.


Assuntos
Carcinoma in Situ/epidemiologia , Infertilidade Masculina/epidemiologia , Neoplasias Testiculares/epidemiologia , Adolescente , Adulto , Biópsia , Carcinoma in Situ/patologia , Dinamarca/epidemiologia , Humanos , Infertilidade Masculina/patologia , Masculino , Pessoa de Meia-Idade , Oligospermia/epidemiologia , Oligospermia/patologia , Prevalência , Estudos Prospectivos , Neoplasias Testiculares/patologia
13.
Small Rumin Res ; 40(1): 73-82, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11259878

RESUMO

During the breeding season, 42 adult German Improved Fawn nanny goats were superovulated with a single dose of pFSH, hMG or eCG at the end or a single application of pFSH 36h before the end of synchronization treatment using flugestone acetate (FGA). Plasma sampling was performed immediately before and 1h after gonadotrophin treatment, twice daily during pre-estrus and estrus and once daily during post-estrus in order to determine peripheral estradiol-17beta and progesterone levels. During that period, ovarian dynamics was followed by serial ultrasound scans (8h interval during pre-estrus and estrus and once daily during post-estrus). Estradiol-17beta profiles differed between the treatment groups exhibiting significantly positive correlations between the mean estradiol-17beta concentrations and the numbers of developing large and medium-sized follicles during estrus. The early bolus application of FSH 36h before the end of synchronization treatment induced an additional advanced estradiol-17beta peak during gestagen dominance. A sharp decrease of estradiol-17beta at the end of estrus seems to play a major role for normal luteal development. Progesterone profiles during the early luteal phase revealed high premature luteal regression. An early progesterone increase was accompanied by low premature regression rates.Although simple B-mode ultrasonography is suitable to follow follicular growth patterns and to determine the ovulation rate following different superovulation regimen endocrinological supervision is required in order to detect a premature corpus luteum insufficiency.

14.
Small Rumin Res ; 40(1): 83-93, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11259879

RESUMO

During the breeding season, 42 adult German Improved Fawn nanny goats were superovulated with a single administration of pFSH, hMG or eCG at the end or a single dose of pFSH 36h before the end of estrus synchronization. Development of follicles and corpora lutea were observed by ultrasonic scanning of the ovaries every 8h from gonadotrophin treatment, until the end of estrus and once daily for the following 6 days. Differences in follicular dynamics could be realized in the four superovulation groups, and the duration of the stimulatory action following the single gonadotrophin challenge was estimated to last for 40-72h in the case of pFSH and to exceed 72h in the case of hMG and eCG treatment groups. Corpora lutea could first be detected 3 days after estrus, whereas an exact count was not possible until day 6. The ovulation rates were satisfactory, suggesting that a single injection of pFSH or hMG provides an adequate stimulus to induce a superovulatory reaction. Premature regression of corpora lutea could not be identified ultrasonographically at these early stages of the luteal phase. However, ultrasonography is a suitable method to follow follicular dynamics after superovulation and to estimate the superovulatory response in goats.

15.
Artigo em Alemão | MEDLINE | ID: mdl-10077816

RESUMO

Investigations in different species including the horse have demonstrated that prostaglandin F2 alpha (PGF2 alpha) is involved in initiating uterine contractions occurring during mating and artificial insemination (A.I.). Uterine contractions play an important role with respect to the sperm transport within the female genital tract. The objective of the present investigation was to evaluate whether the administration of PGF2 alpha (Dinoprost) synchronously to A.I. could have a positive effect on the pregnancy rate in mares. A field study including 346 warmblood-mares (age two to 20 years) belonging to a private studfarm was conducted during the breeding season 1996. The mares were assigned to two groups, group A: mares with spontaneous ovulation, group B: mares in which the ovulation was induced by a GnRH-analog-implant (Deslorelin). PGF2 alpha (Dinoprost) was administered either intramusculary (i.m., 5.0 mg) or intrauterine (i.ut., 0.5 mg diluted in 1.9 ml isotonic NaCl-solution and added to the semen dosis). The study was carried out in a double-blind fashion using isotonic NaCl-solution as a placebo. The mares of each group were randomly assigned to one of the two treatments (i.m. vs. i.ut.). The following first cycle pregnancy rates (day 18) were obtained in mares treated and inseminated once per oestrus: group A1 (PGF2 alpha, i.m.): 54.5% (n = 33); group A2 (placebo, i.m.): 69.7% (n = 33); group A3 (PGF2 alpha, i.ut.): 65.4% (n = 26); group A4 (placebo, i.ut.): 69.8% (n = 32); group B1 (PGF2 alpha, i.m.): 56.5% (n = 46); group B2 (placebo, i.m.): 29.6% (n = 27); group B3 (PGF2 alpha, i.ut.): 66.7% (n = 45); group B4 (placebo, i.ut.): 60.0% (n = 30). The pregnancy rates did not differ between the different groups with the exception of group B2 (p < 0.05). In mares treated repeatedly during the oestrus period (group A, n = 88; group B, n = 23), the pregnancy rates did not differ significantly between treatment and control groups. From the results obtained it is concluded that the PGF2 alpha-application did not show an effect on the pregnancy rate. Further factors influencing the results to a small degree were the stallions, semen age and quality and frequency of insemination per oestrus.


Assuntos
Dinoprosta/farmacologia , Fertilização/efeitos dos fármacos , Hormônio Liberador de Gonadotropina/análogos & derivados , Inseminação Artificial/veterinária , Prenhez , Animais , Dinoprosta/administração & dosagem , Implantes de Medicamento , Feminino , Hormônio Liberador de Gonadotropina/administração & dosagem , Hormônio Liberador de Gonadotropina/farmacologia , Cavalos , Inseminação Artificial/métodos , Ovulação/efeitos dos fármacos , Ovulação/fisiologia , Indução da Ovulação/métodos , Indução da Ovulação/veterinária , Gravidez , Pamoato de Triptorrelina/análogos & derivados
16.
Dtsch Tierarztl Wochenschr ; 103(8-9): 328-31, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-9011501

RESUMO

The protein pattern of individual porcine oocytes matured as intact cumulus oocyte complexes either in vivo or in vitro with or without FSH and LH for 43 h were investigated. The synthesis of a 53 kDa polypeptide ceased 21 h after hCG administration whereas a 44 kDa polypeptide were consistently absent in the protein patterns of nearly all of the in vivo maturing oocytes. Further on, a polypeptide with a relative molecular weight of 46000 persisted throughout maturation. A precipitous increase in the synthesis of two other proteins with relative molecular weights of 38000 and 28000, respectively, was observed at 9 and 21 h after hCG injection. In in vitro matured oocytes with or without FSH and LH the synthesis of the 53 kDa band decreased after a culture period of 9h. Further on, the production of the 44 kDa polypeptide ceased only in oocytes incubated in FSH and LH supplemented media after 21 h of culture. On the other hand, the two proteins of Mr 38000 and 28000 appeared only in most of the protein profiles of oocytes cultured with FSH and LH for 43 h. The production of the 46 kDa polypeptide during a 21 h culture period was significantly affected by the presence of additional granulosa cells in connection with the cumulus oocyte complex. Neither the appearance nor the disappearance of the 5 investigated bands was influenced by the presence or absence of the germinal vesicle after 21 h of culture. It is concluded that at least the addition of FSH and LH to the culture medium is necessary for cumulus oocytes complexes to synthesize a protein pattern closely corresponding to that produced by in vivo matured oocytes.


Assuntos
Oócitos/metabolismo , Biossíntese de Proteínas , Suínos/fisiologia , Animais , Feminino , Hormônio Foliculoestimulante/metabolismo , Células da Granulosa/fisiologia , Técnicas In Vitro , Hormônio Luteinizante/metabolismo , Oócitos/crescimento & desenvolvimento
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