scholarly journals 150 ENVIRONMENT OF THE EARLY EMBRYO AND ITS EFFECT ON DEVELOPMENT AND POSTNATAL LIFE

2005 ◽  
Vol 17 (2) ◽  
pp. 225
Author(s):  
A. Watkins ◽  
A. Wilkins ◽  
T. Papenbrock ◽  
C. Osmond ◽  
M. Hanson ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Systolic Blood Pressure ◽  
Embryo Transfer ◽  
Litter Size ◽  
Early Embryo ◽  
Blastocyst Development ◽  
Treatment Groups ◽  
Elevated Systolic Blood Pressure

We have investigated the impact of mouse early embryo in vitro culture environment on (a) short-term blastocyst development and (b) long-term postnatal growth and physiology after embryo transfer. In vitro-developed blastocysts, cultured from the 2-cell stage, had reduced inner cell mass (ICM) and trophectoderm (TE) cell numbers when compared to in vivo-derived blastocysts at 96 h post-hCG (n = 13–39, P < 0.05). Despite the retardation in blastocyst development, the ICM:TE ratio was equivalent in both treatment groups. Using embryo transfer techniques, we compared the postnatal development of embryos cultured in vitro from the 2-cell to the blastocyst stage (termed “in vitro” mice) with offspring generated from blastocysts developed in vivo, but which also underwent embryo transfer (termed “in vivo” mice). These two treatment groups were in turn compared with mice derived from naturally mated mothers, which had their mean litter size at birth adjusted to a size comparable with that of the in vitro and in vivo mice (a mean of 6 animals) and which had not been transferred. All data were analyzed using a multilevel random effects regression model which took into account between-mother and within-mother variation in litter size for parameters measured from individual animals. No significant differences in birth weight were observed between in vitro and in vivo offspring. However, in vitro offspring were significantly lighter than in vivo offspring in a gender-dependent manner at 2 weeks of age (males, P = 0.009) and at 6 and 11 weeks of age (females, P = 0.037 and 0.035, respectively). In addition, at 4 weeks of age, the in vivo males became significantly lighter when compared to the naturally mated males (P = 0.034). At 8 weeks of age, the in vivo females had a significantly elevated systolic blood pressure when compared to the in vitro females (P = 0.003); however, at 21 weeks of age, both in vitro males and females had a significantly elevated blood pressure when compared to in vivo offspring (P < 0.003). At 8, 15, and 21 weeks of age, offspring derived from transferred embryos developed with significantly elevated systolic blood pressure when compared to non-embryo transfer offspring (P < 0.05). No significant differences in serum angiotensin-converting enzyme activity (a potent regulator of systolic blood pressure) was observed between the treatment groups. Significantly altered liver:body weight ratios were observed between the in vitro and in vivo males, and between the in vitro and the naturally mated (6) females (P < 0.038). All of the above data are independent of litter size. These data support the hypothesis that early embryo environment can influence postnatal growth and cardiovascular physiology. This research was funded by an MRC research grant to TPF, and by a DOHaD studentship.

100 EMBRYO SURVIVAL AND CONCEPTUS ELONGATION FOLLOWING ASYNCHRONOUS EMBRYO TRANSFER IN CATTLE

2015 ◽  
Vol 27 (1) ◽  
pp. 143
Author(s):  
F. Randi ◽  
B. Fernandez ◽  
M. McDonald ◽  
C. Johnson ◽  
N. Forde ◽  
...  
Keyword(s):  
Embryo Transfer ◽  
Prostaglandin F2α ◽  
Early Embryo ◽  
Embryo Survival ◽  
Treatment Groups ◽  
Length Data ◽  
Uterine Environment ◽  
To Receive ◽  
Intravaginal Device

Maternal progesterone (P4) regulates early conceptus growth and development in ruminants. Early embryo transfer studies in sheep and cattle demonstrated a need for close synchrony between the embryo and the uterine environment of the recipient. However, manipulating P4 may be one way of strategically regulating the temporal changes that normally occur in the uterine environment in order to allow flexibility in the timing of embryo transfer. For example, previous studies have demonstrated that P4 administration during the first few days of the oestrous cycle facilitates pregnancy establishment with older embryos. The aim of this study was to examine the effect of embryo-uterine synchrony on conceptus elongation in cattle. Oestrous cycles of crossbred beef heifers were synchronised using an 8-day P4-Releasing Intravaginal Device (PRID Delta®, CEVA, Mountain View, CA, USA) with administration of a prostaglandin F2α analogue (Enzaprost®, CEVA; 5 mL equivalent to 25 mg of dinoprost) given on the day before PRID removal. Heifers were checked for signs of oestrus 4 times per day commencing 30 h after PRID withdrawal. Only those seen in standing oestrus (n = 50) were randomly assigned to 1 of 5 treatment groups to receive Day 7 in vitro-produced blastocysts (n = 10 per recipient) (1) on Day 5 post-oestrus; (2) on Day 5, with P4 supplementation via PRID from Day 3 to 5 + 750 IU of eCG at PRID insertion; (3) on Day 5, PRID Delta from Day 3 to 5 plus 3000 IU of hCG at PRID insertion; (4) on Day 7, or (5) on Day 9. At embryo age Day 14, all heifers were slaughtered and the uterus was flushed to recover and measure conceptuses. Data are summarised in Table 1. Fewer recipients yielded conceptuses (P < 0.05) and fewer conceptuses overall were recovered (P < 0.05) following transfer on Day 5 compared with Day 7 or Day 9. Supplementation with P4 resulted in short cycles (evidenced by corpus luteum regression and/or a recent ovulation at slaughter) in 33.3 to 54.5% of recipients receiving embryos on Day 5. Mean conceptus length was greater (P < 0.05) following transfer to an advanced uterus. In conclusion, transfer of embryos to a retarded (Day 5) uterine environment results in poor embryo survival. Supplementation with P4 shortened the interoestrous period in a significant number of heifers. Transfer to an advanced uterine environment promotes conceptus elongation, presumably driven by P4. Table 1.Embryo survival and conceptus length data

Ligustilide Reduces Phenylephrine Induced-Aortic Tension In Vitro but has No Effect on Systolic Pressure in Spontaneously Hypertensive Rats

2007 ◽  
Vol 35 (03) ◽  
pp. 487-496 ◽  
Author(s):  
Jun-Rong Du ◽  
Yan Yu ◽  
Yao Yao ◽  
Bo Bai ◽  
Xu Zong ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Essential Oil ◽  
Systolic Blood Pressure ◽  
Systolic Pressure ◽  
Reduce Blood Pressure ◽  
Shr Rats ◽  
Spontaneously Hypertensive ◽  
Long Time

Radix Angelica sinensis, known as Danggui in Chinese, has been used to treat cardiovascular diseases in traditional Chinese medicine for a long time. Experimental evidence showed that the essential oil of Danggui could reduce blood pressure in rabbits, cats or hypertensive dogs when given intravenously. In this study, we investigated the effects of Z-ligustilide, the main lipophilic component of the essential oil of Danggui on aortic tension induced by phenylephrine, an alpha-adrenergic agonist, in vitro and the systolic blood pressure in SHR rats. We demonstrated for the first time that ligustilide can significantly reduce the phenylephrine-induced aortic tension in vitro with IC50 about 64 μg/ml, but has no in vivo effect on systolic blood pressure in SHR rats when administrated orally. The data on transport of ligustilide across Caco-2 monolayer suggested an efficient intestinal absorption of ligustilide in vivo, implying that the non-effectiveness of ligustilide in vivo is not due to the poor absorption in the gastrointestinal tract. Further studies on whether ligustilide is one of the main anti-hypertensive components of the essential oil are needed.

Normoprolactinaemia in spontaneously hypertensive rats: absence of a close relationship between plasma concentrations of prolactin and systolic blood pressure

1990 ◽  
Vol 125 (3) ◽  
pp. 359-364 ◽  
Author(s):  
E. Aguilar ◽  
M. L. Rodríguez-Padilla ◽  
L. Pinilla
Keyword(s):  
Blood Pressure ◽  
Systolic Blood Pressure ◽  
Plasma Concentrations ◽  
Male Rats ◽  
Adult Males ◽  
Spontaneously Hypertensive ◽  
Close Relationship ◽  
Wistar Kyoto

ABSTRACT Prolactin has been involved in different types of hypertension both in man and in rats. In an attempt to substantiate this hypothesis, we have analysed the correlation between plasma concentrations of prolactin and systolic blood pressure (SBP) in female and male rats from spontaneously hypertensive (SH) and normotensive Wistar–Kyoto strains (30, 60 and 90 days old), as well as in adult female Wistar rats rendered hyperprolactinaemic by the administration of 100 μg testosterone propionate on day 1 of life, or adult males with low plasma concentrations of prolactin after administration of bromocriptine (4 mg/kg per day) over 15 days. Our results indicate a lack of correlation between plasma concentrations of prolactin and SBP since plasma concentrations of prolactin were normal in male and female SH rats and hyper- and hypoprolactinaemia did not affect SBP. In spite of these normal plasma concentrations of prolactin, SH rats showed subtle changes in the secretion of this hormone in vitro and in vivo in response to exogenous serotonin administration and to immobilization. Journal of Endocrinology (1990) 125, 359–364

scholarly journals Birth of lambs of a pre-determined sex after in vitro production of embryos using frozen–thawed sex-sorted and re-frozen–thawed ram spermatozoa

Reproduction ◽  
2004 ◽  
Vol 127 (5) ◽  
pp. 557-568 ◽  
Author(s):  
F K Hollinshead ◽  
G Evans ◽  
K M Evans ◽  
S L Catt ◽  
W M C Maxwell ◽  
...  
Keyword(s):  
High Speed ◽  
Gradient Centrifugation ◽  
In Vitro Production ◽  
Blastocyst Development ◽  
Embryo Survival ◽  
Treatment Groups ◽  
Sperm Migration ◽  
And Control

The characteristics and functional capacity of ram spermatozoa frozen–thawed prior to and after flow cytometric sorting was assessed after incubation (37 °C; 6 h),in vitrofertilisation (IVF), and transfer of fresh and vitrifiedin vitroproduced embryos. Frozen-thawed spermatozoa from two rams were allocated to four treatment groups: (i) non-sorted (Control); (ii) sorted (FS); (iii) sorted then re-frozen (FSF) and (iv) re-frozen control (FCF). Frozen-thawed samples were separated into X- and Y-chromosome bearing spermatozoa using a high-speed sperm sorter after density gradient centrifugation (X: 88 ± 1.5% and Y: 87 ± 1.1% purity). After 6 h incubation (37 °C), the percentage of motile spermatozoa was higher (P< 0.001) for FS (84 ± 2.0%) compared with all other treatments (Control: 36 ± 3.3%, FSF: 28 ± 3.1%, FCF: 20 ± 2.0%). In a sperm migration test greater numbers of FS spermatozoa penetrated 5 mm into the artificial cervical mucus compared with spermatozoa from all other treatments (152 ± 39.4 vs 31 ± 9.2 spermatozoa respectively;P< 0.05). Fertilisation and cleavage rates were higher (P< 0.05) forin vitromatured oocytes inseminated with Control compared with FSF spermatozoa. However, the Day 7 blastocyst development rate was higher for oocytes inseminated with FSF (62.2%) than FS and Control spermatozoa (52.7 and 50.0%;P< 0.05). The number of ewes pregnant (Day 60), lambing and thein vivoembryo survival rate was greater (P< 0.01) after the transfer of fresh embryos rather than vitrified embryos derived from X- and Y-spermatozoa (67.6, 64.7 and 41.2% vs 29.6, 25.9 and 14.8% respectively). Twenty-six of the 30 (86.7%) lambs derived from sex-sorted spermatozoa were of the correct sex. These results demonstrate that frozen–thawed ram spermatozoa can be sex-sorted for immediate or future use after re-cryopreservation and, in conjunction with IVF and embryo transfer, can be used to efficiently produce offspring of pre-determined sex.

208 IN VITRO FERTILIZATION UNDER SIMULATED STRESS AND SUBSEQUENT IN VITRO EMBRYO PRODUCTION IN THE PIG

2011 ◽  
Vol 23 (1) ◽  
pp. 203
Author(s):  
R. González ◽  
Y. Brandt
Keyword(s):  
Cumulus Cells ◽  
Early Embryo ◽  
Reproductive Hormones ◽  
Blastocyst Development ◽  
Cleavage Rate ◽  
Vitro Fertilization ◽  
Endocrine Profile ◽  
Serum Gonadotropin

Fertilization is a crucial step for successful reproduction and can be negatively influenced by stressful situations. It is generally accepted that stress affects reproduction, altering the endocrine profile of the female. An altered hormonal environment where the oocyte is developing could affect critical processes such as fertilization. Using a mixed in vivo–in vitro system, we assessed the ability of the oocyte to undergo fertilization and early development after exposure to blood plasma from sows that had experienced simulated stress through repeated injections of adrenocorticotropic hormone (ACTH) before ovulation (known concentrations of cortisol and reproductive hormones as well as exact ovulation time assessed by ultrasonography). Oocytes (n = 926, 7 replicates) collected from abattoir ovaries were matured in TCM-199 with BSA supplemented with hormones (10 IE mL–1 of pregnant mare serum gonadotropin and 5 IE mL–1 of hCG) and insulin-transferrin-selenium (5 μL mL–1) for 24 h, followed by 22 h without supplements. During IVF, gametes were exposed to 10% of pooled plasma (n = 3 per treatment) collected approximately 1 h before ovulation from ACTH-treated sows (A group), nontreated control sows (C group), or media with BSA (B group) for 24 h. Fresh semen was added at 5 × 105 cells mL–1. Afterward, the remaining cumulus cells and sperm were removed from oocytes by vortexing (1 min), and presumptive zygotes were placed in culture medium (porcine zygote medium). Cleavage rate was assessed at 48 h post-insemination (hpi) and the embryos (n = 433, 7 replicates) were cultured up to Day 7 and stained with Hoechst 33342 (10 μg mL–1) to count the total number of nuclei. In addition, non-cleaved oocytes were stained at 48 hpi with Hoechst to assess sperm-zona binding. Binding to the zona was assessed only in oocytes found to be matured. Statistical analysis was done using Kruskal-Wallis ANOVA and the Mann-Whitney U test. The number of spermatozoa bound to the zona pellucida was higher in the B group, and binding was notably negatively affected in the ACTH group (0.43 ± 0.18, 35.93 ± 2.50, and 3.44 ± 1.04 for the A, B, and C group, respectively; P < 0.001). Cleavage rate (over total number of presumptive zygotes) in the A group (30.71 ± 3.76%) was significantly lower than in the control groups (59.93 ± 4.0 and 52.2 ± 5.31% for the B and C group, respectively; P < 0.01). Blastocyst rate expressed over the total number of embryos was reduced in the A group (9.40 ± 5.20%) compared with the controls (27.10 ± 5.79 and 25.66 ± 5.28% in the B and C group, respectively; P < 0.05). However, no differences were found in the total number of nuclei in the blastocysts. The results suggest that fertilization is a sensitive event that could be negatively influenced by stress, subsequently affecting early embryo development. A reduced number of spermatozoa attached to the zona and a lower number of embryos and lower blastocyst development were observed in the simulated-stress group. Further studies would help to elucidate which (in the oocyte, spermatozoon, or both) mechanisms are being affected by ACTH-simulated stress around fertilization. Data are expressed as mean ± SEM. Funded by Formas.

scholarly journals 233EXPRESSION OF INSULIN-LIKE GROWTH FACTOR (IGF) MRNA IN BOVINE CONCEPTUSES FROM EMBRYOS PRODUCED IN VIVO OR IN VITRO

2004 ◽  
Vol 16 (2) ◽  
pp. 237
Author(s):  
C.E. Farin ◽  
J.E. Alexander ◽  
K.F. Rodriguez ◽  
P.W. Farin
Keyword(s):  
Mrna Expression ◽  
Agricultural Research ◽  
Pcr Analysis ◽  
Blastocyst Development ◽  
Globin Mrna ◽  
Treatment Groups ◽  
The North ◽  
Gapdh Mrna

The objective of this study was to determine the effect of in vitro embryo production (IVP) on expression of mRNAs for IGF-1, IGF-2, IGF-1 receptor (IGF-1R), IGF-2R and GAPDH in bovine conceptuses at Day 17 of gestation. In vivo embryos (In vivo) were recovered from superovulated Holstein cows. For IVP, Holstein oocytes were matured, fertilized and then cultured in M199 with 10% serum (IVPS) or 1% BSA (IVPSR) to 72hpi. All embryos were then transferred to M199 with 10% serum and cultured to 168hpi. The same Holstein sire was used to produce all embryos. Single grade 1 blastocysts were transferred into recipient heifers. On day 10 after transfer, conceptuses were recovered, measured and stored at −80°C prior to extraction of whole cell (wc) RNA and genomic (g) DNA. wcRNA was assessed for quality based on A260/A280 ratio and visualization of 18S and 28S ribosomal RNA. Only complete (intact) conceptuses with at least 10μg high-quality wcRNA recovered after extraction were included in the analysis (In vivo, n=8; IVPS n=8; IVPSR n=7). Conceptus sex was determined by PCR analysis of gDNA. Semi-quantitative PCR assays were used to assess relative expression of all mRNAs. For each conceptus, 2μg wcRNA were mixed with 3pg rabbit globin mRNA, DNase-treated and reverse-transcribed using random hexamers. Conceptus cDNA samples (140ng each for IGF-1, IGF-2 mRNAs;; 100ng each for IGF-1R, IGF-2R, GAPDH and globin mRNAs) were assayed in duplicate within single assays. Relative mRNA expression was calculated as the ratio of band intensities representing the mRNA of interest to globin mRNA. All data were analyzed for effects of treatment (In vivo, IVPS, IVPSR or In vivo, IVP), sex, stage of blastocyst development at transfer (early, mid, expanded) and the interactions of treatment sex and treatment stage. Conceptus length (LSM±SEMmm) did not differ with treatment (In vivo: 182±55; IVPS: 257±47; IVPSR: 310±72). Expression of GAPDH mRNA was greater (P=0.02) in female conceptuses (1.31±0.11) than in males (0.96±0.07) and did not differ (P=0.14) between treatment groups (In vivo: 1.30±0.11, IVPS: 1.00±0.09, IVPSR: 1.10±0.14). However, when the IVP groups were combined and compared to In vivo controls, expression of GAPDH mRNA was both greater (P=0.002) in females (1.38±0.10) than in males (0.94±0.06) and differed (P=0.03) with treatment (In vivo: 1.30±0.10, IVP: 1.01±0.07). Expression of IGF-1 and IGF-2 mRNA was not detected in the majority of conceptuses. Expression of IGF-1R mRNA was greater (P=0.02) in female (1.19±0.10) than in male conceptuses (0.87±0.07) and differed (P=0.02) with stage of blastocyst development at transfer (early: 0.79±0.07; mid: 1.23±0.13; expanded: 1.07±0.11). There was no effect of treatment on expression of IGF-1R mRNA. Expression of IGF-2R mRNA differed (P=0.03) with treatment (In vivo: 0.85±0.10; IVPS: 0.76±0.09; IVPSR: 0.33±0.13). In conclusion, expression of both imprinted and non-imprinted genes is altered in conceptuses resulting from embryos produced in vitro. Supported by the North Carolina Agricultural Research Service.

166 CAN COXIELLA BURNETII BE TRANSMITTED BY GOAT EMBRYO TRANSFER?

2013 ◽  
Vol 25 (1) ◽  
pp. 231
Author(s):  
A. Alsaleh ◽  
J. L. Pellerin ◽  
C. Roux ◽  
M. Larrat ◽  
G. Chatagnon ◽  
...  
Keyword(s):  
Embryo Transfer ◽  
Coxiella Burnetii ◽  
Q Fever ◽  
Early Embryo ◽  
Embryonic Cells ◽  
Bovine Embryos ◽  
Tissue Samples ◽  
Worldwide Distribution

Coxiella burnetii, an obligate intracellular bacterium of worldwide distribution, is responsible for Q fever. Detection of significant bacterial loads in flushing media and tissue samples (oviducts and uterine horns) from the genital tracts of nonpregnant goats is a risk factor for in utero infection and transmission during embryo transfer (Alsaleh et al. 2011 CIMID 34, 355–360). The aim of this study was to investigate (1) whether cells of early goat embryos isolated from in vivo fertilized goats interact with C. burnetii in vitro, (2) whether the embryonic zona pellucida (ZP) protects early embryo cells from infection, and (3) the efficacy of the washing protocol recommend by the IETS for bovine embryos. The study was performed in triple replicate: 12 donor goats, certified negative by ELISA and PCR, were synchronized, superovulated, and subsequently inseminated by Q fever-negative males. Sixty-eight embryos were collected 4 days later by laparotomy. Two-thirds of the resulting ZP-intact and ZP-free 8- to 16-cell embryos (9–9, 11–11, and 4–4 in replicates 1, 2, and 3, respectively) were placed in 1 mL of MEM containing 107 C. burnetii CBC1 (IASP, INRA Tours). After overnight incubation at 37°C and 5% CO2, the embryos were washed according to the IETS procedure. In parallel, the remaining third ZP-intact and ZP-free uninfected embryos (3–3, 5–5, and 2–2 in replicates 1, 2, and 3, respectively) were submitted to the same procedures but without C. burnetii, thus serving as controls. The 10 washing fluids for all batches of each replicate were collected and centrifuged for 1 h at 13 000g. The washed embryos and pellets were tested by PCR. Coxiella burnetii DNA was found in all batches of ZP-intact and ZP-free infected embryos after 10 successive washes. It was also detected in the first 5 washing fluids for ZP-free embryos and in the first 8 washing fluids for ZP-intact embryos. None of the control batches (embryos and washing fluids) were found to contain bacterial DNA. These results clearly demonstrate that caprine early embryonic cells are susceptible to infection by C. burnetii. The bacterium shows a strong tendency to cling to the ZP after in vitro infection, and the washing procedure recommended by the IETS for bovine embryos failed to remove it. The persistence of these bacteria makes the embryo a potential means of transmission to recipient goats. Further studies are needed to investigate whether the enzymatic treatment of caprine embryos infected by C. burnetii would eliminate the bacteria from the ZP.

162 CAN CHLAMYDIA ABORTUS BE TRANSMITTED BY EMBRYO TRANSFER IN GOATS?

2015 ◽  
Vol 27 (1) ◽  
pp. 172
Author(s):  
J. L. Pellerin ◽  
A. Ashraf ◽  
M. Oseikria ◽  
K. Laroucau ◽  
F. Vorimore ◽  
...  
Keyword(s):  
Embryo Transfer ◽  
Early Embryo ◽  
Bovine Embryos ◽  
Chlamydia Abortus ◽  
Zoonotic Risk ◽  
Embryo Cells ◽  
Means Of Transmission ◽  
Infectious Form

Chlamydia abortus is a gram-negative obligate intracellular bacterium. Its lifecycle includes a resistant infectious form and a metabolically active non-infectious form. Chlamydia abortus infection results in abortion in goats; in nonpregnant animals the infection is usually subclinical. Chlamydia abortus presents a major zoonotic risk for pregnant women. The aim of this study was to investigate whether the embryonic zona pellucida (ZP) protects early embryo cells from infection and to test the efficacy of the washing protocol recommended by the IETS for bovine embryos. The study was performed in triple replicate: 14 donor goats, certified negative by ELISA and PCR to C. abortus, were synchronized, superovulated, and subsequently inseminated by males controlled negative for C. abortus. Fifty-two ZP-intact embryos (8–16 cells) were collected 4 days later, by laparotomy. The embryos were randomly divided into 12 batches. Nine batches of 5 embryos were incubated in a medium containing 4 × 107 Chlamydia mL–1, AB7 strain. After incubation for 18 h at 37°C in an atmosphere of 5% CO2, the embryos were washed in batches in 10 successive baths of PBS and 5% FCS solution in accordance with IETS guidelines for bovine embryos. In parallel, 3 batches of ZP-intact embryos (2, 2, and 3 embryos in the first, second, and third batches, respectively) were used as controls by being subjected to similar procedures, but without exposure to C. abortus. The 10 wash baths were collected separately and centrifuged for 1 h at 13 000 × g. The washed embryos and the pellets of the 10 centrifuged wash baths were frozen at –20°C before examination for evidence of C. abortus using RT-PCR. Chlamydia abortus DNA was found in all batches of infected ZP-intact embryos (9/9) after 10 successive washes. It was also detected in the tenth wash fluid for 4 batches (4/9) of infected embryos. As expected, none of the embryos or their washing fluids in the control batches were DNA positive. These results demonstrate that C. abortus adheres to and/or penetrates the ZP of in vivo caprine embryos after in vitro infection, and that the standard washing protocol recommended by the IETS for bovine embryos failed to remove it. The persistence of these bacteria after washing makes the embryo a potential means of transmission of the bacterium during embryo transfer from infected donor goat to healthy recipients and/or their offspring. Further studies are required to investigate whether enzymatic and/or antibiotic treatment of infected caprine embryos can eliminate C. abortus from the ZP.

Comparison of two approaches to nuclear transfer in the bovine: hand-made cloning with modifications and the conventional nuclear transfer technique

2005 ◽  
Vol 17 (5) ◽  
pp. 573 ◽  
Author(s):  
R. Tayfur Tecirlioglu ◽  
Melissa A. Cooney ◽  
Ian M. Lewis ◽  
Natasha A. Korfiatis ◽  
Renee Hodgson ◽  
...  
Keyword(s):  
Cell Lines ◽  
Nuclear Transfer ◽  
Cell Number ◽  
Developmental Competence ◽  
Blastocyst Development ◽  
Total Cell Number ◽  
Treatment Groups ◽  
Fusion Efficiency

The aim of the present study was to compare the in vitro and in vivo developmental competence of hand-made cloning (HMC) embryos with the conventional nuclear transfer (NT) method using five somatic cell lines and in vitro-fertilised (IVF; control) embryos. Modifications to the HMC procedure included fusion efficiency optimisation, effect of cytoplasmic volume and cloned embryo aggregation. The developmental competence of blastocysts from each of the treatment groups and cell lines used was assessed following transfer to 345 recipients. Vitrification was also used to enable management of recipient resources and to assess the susceptibility of membranes to cryopreservation following zona removal. Increasing cytoplasmic volume to 150% or aggregating two embryos improved the blastocyst development rate and increased the total cell number. Although HMC embryo transfers established a significantly higher pregnancy rate on Day 30 than fresh IVF or NT embryo transfers, the overall outcome in terms of cloned live births derived from either fresh or vitrified/thawed HMC or NT embryo transfers across the five cell lines did not differ. The birth and continued survival of clones produced with HMC technology with equivalent efficiency to NT shows that it can be used as an alternative method for the generation of cloned offspring in the bovine.

Exaggerated exercise pressor reflex in adults with moderately elevated systolic blood pressure: role of purinergic receptors

2014 ◽  
Vol 306 (1) ◽  
pp. H132-H141 ◽  
Author(s):  
Jody L. Greaney ◽  
Evan L. Matthews ◽  
Mary E. Boggs ◽  
David G. Edwards ◽  
Randall L. Duncan ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Purinergic Receptors ◽  
P2 Receptor ◽  
Drg Neurons ◽  
Exercise Pressor Reflex ◽  
Elevated Systolic Blood Pressure ◽  
Pressor Reflex

The neurocirculatory responses to exercise are exaggerated in hypertension, increasing cardiovascular risk, yet the mechanisms remain incompletely understood. The aim of this study was to examine the in vitro effectiveness of pyridoxal-5-phosphate as a purinergic (P2) receptor antagonist in isolated murine dorsal root ganglia (DRG) neurons and the in vivo contribution of P2 receptors to the neurocirculatory responses to exercise in older adults with moderately elevated systolic blood pressure (BP). In vitro, pyridoxal-5-phosphate attenuated the ATP-induced increases in [Ca2+]i (73 ± 15 vs. 11 ± 3 nM; P < 0.05). In vivo, muscle sympathetic nerve activity (MSNA; peroneal microneurography) and arterial BP (Finometer) were assessed during exercise pressor reflex activation (static handgrip followed by postexercise ischemia; PEI) during a control trial (normal saline) and localized P2 receptor blockade (pyridoxal-5-phosphate). Compared with normotensive adults (63 ± 2 yr, 117 ± 2/70 ± 2 mmHg), adults with moderately elevated systolic BP (65 ± 1 yr, 138 ± 5/79 ± 3 mmHg) demonstrated greater increases in MSNA and BP during handgrip and PEI. Compared with the control trial, local antagonism of P2 receptors during PEI partially attenuated MSNA (39 ± 4 vs. 34 ± 5 bursts/min; P < 0.05) in adults with moderately elevated systolic BP. In conclusion, these data demonstrate pyridoxal-5-phosphate is an effective P2 receptor antagonist in isolated DRG neurons, which are of particular relevance to the exercise pressor reflex. Furthermore, these findings indicate that exercise pressor reflex function is exaggerated in older adults with moderately elevated systolic BP and further suggest a modest role of purinergic receptors in evoking the abnormally large reflex-mediated increases in sympathetic activity during exercise in this clinical population.

Sign in / Sign up

Export Citation Format

Share Document