Effect of post-mating GnRH analogue (buserelin) treatment on PGF2α release in ewes and ewe lambs

AbstractAn investigation was conducted into the effect of buserelin treatment on day 12 post mating on ovarian function and plasma progesterone and oestradiol-17 ji concentration in ewes. Changes in ovarian structures were determined, at laparoscopy or after slaughter, 48 h after treatment in 38 control and 41 ewes given an injection of 4 jig buserelin on day 12 post mating (day 0 = day of oestrus). Ovulation rate was higher in buserelin treated (2·76) than in control (1·87) ewes (P < 0·05). Moreover, 41 of the 113 corpora lutea observed in the buserelin group were the result of ovulations that had occurred within 48 h post treatment, compared with two of 71 in the controls (P < 0·05). Blood samples were collected from 10 ewes in each treatment group for hormone analysis. Mean progesterone concentrations tended to be higher, in samples collected from 2 to 6h post treatment, in the buserelin group (4·31 (s.e. 1·32) p.g/1) compared with the control group (3·71 (s.e. 1·44) fig/l. Furthermore, overall mean oestradiol concentrations were lower, during days 13, 14 and 15 post mating, in buserelin treated (0·72 (s.e. 0·26) ngfl) than in control (0·94 (s.e. 0·50) ng/l) ewes (P < 0·05). The results of this study indicate that buserelin treatment on day 12 post mating changes ovarian function.

Download Full-text

The effect of treatment with a gonadotrophin releasing hormone on the fertility of beef cows

Proceedings of the British Society of Animal Science ◽

10.1017/s1752756200592679 ◽

1996 ◽

Vol 1996 ◽

pp. 67-67

Author(s):

Duncan Pullar ◽

Anthony Wrathall

Keyword(s):

Beef Cows ◽

Dairy Herds ◽

Gnrh Analogue ◽

Reproductive Disorders ◽

Releasing Hormone ◽

History Of ◽

Buserelin Treatment ◽

Effect Of Treatment ◽

Gonadotrophin Releasing Hormone ◽

Friesian Cows

Use of the gonadotrophin releasing hormone (GnRH) analogue, buserelin has been shown to be effective reducing embryo mortality, by a luteoprotective mechanism, in reproductively normal dairy cows. Drew and Peters, (1991) increased mean pregnancy rates to AI from 53.4 to 65.4% in dairy herds by a buserelin treatment, given 10-12 post service. The objective of this experiment was to determine whether buserelin can also have a beneficial effect on pregnancy rate, in normal and known problem suckler cows.Seventy-eight Hereford x Friesian cows (from 0-4 parities) were used. Forty were considered reproductively normal ('normal' cows) having calved each year from their first season and currently with a 10 week old calf at-foot; while 38 had a history of reproductive disorders ('suspect' cows) and had not calved in the previous 15 months (May 1994 to July 1995).

Download Full-text

The effect of treatment with a gonadotrophin releasing hormone on the fertility of beef cows

Proceedings of the British Society of Animal Science ◽

10.1017/s0308229600030385 ◽

1996 ◽

Vol 1996 ◽

pp. 67-67

Author(s):

Duncan Pullar ◽

Anthony Wrathall

Keyword(s):

Beef Cows ◽

Dairy Herds ◽

Gnrh Analogue ◽

Reproductive Disorders ◽

Releasing Hormone ◽

History Of ◽

Buserelin Treatment ◽

Effect Of Treatment ◽

Gonadotrophin Releasing Hormone ◽

Friesian Cows

Use of the gonadotrophin releasing hormone (GnRH) analogue, buserelin has been shown to be effective reducing embryo mortality, by a luteoprotective mechanism, in reproductively normal dairy cows. Drew and Peters, (1991) increased mean pregnancy rates to AI from 53.4 to 65.4% in dairy herds by a buserelin treatment, given 10-12 post service. The objective of this experiment was to determine whether buserelin can also have a beneficial effect on pregnancy rate, in normal and known problem suckler cows.Seventy-eight Hereford x Friesian cows (from 0-4 parities) were used. Forty were considered reproductively normal ('normal' cows) having calved each year from their first season and currently with a 10 week old calf at-foot; while 38 had a history of reproductive disorders ('suspect' cows) and had not calved in the previous 15 months (May 1994 to July 1995).

Download Full-text

Proceedings: Ovarian follicles and hormonal characteristics of ewe lambs selected for and against multiple births

Reproduction ◽

10.1530/jrf.0.0360458 ◽

1974 ◽

Vol 36 (2) ◽

pp. 458-459

Author(s):

A. Trounson ◽

W. Chamley ◽

J. Kennedy ◽

R Tassell

Keyword(s):

Ovarian Follicles ◽

Multiple Births ◽

Ewe Lambs

Download Full-text

1675 Ground redberry juniper and urea in supplements fed to Rambouillet ewe lambs on growth, blood serum, and fecal N

Journal of Animal Science ◽

10.2527/jam2016-1675 ◽

2016 ◽

Vol 94 (suppl_5) ◽

pp. 816-816

Author(s):

T. R. Whitney ◽

J. P. Muir

Keyword(s):

Blood Serum ◽

Ewe Lambs

Download Full-text

Evaluation of a New 99mTc-labeled GnRH Analogue as a Possible Imaging Agent for Prostate Cancer Detection

Anti-Cancer Agents in Medicinal Chemistry ◽

10.2174/1871520620666200619175352 ◽

2020 ◽

Vol 20 (14) ◽

pp. 1695-1703

Author(s):

Arezou Masteri Farahani ◽

Fariba Maleki ◽

Nourollah Sadeghzadeh ◽

Saeid Abediankenari ◽

Seyed Mohammad Abedi ◽

...

Keyword(s):

Prostate Cancer ◽

Cell Lines ◽

Cancer Cell ◽

Nude Mice ◽

Normal Saline ◽

Radiochemical Purity ◽

Prostate Cancer Cell ◽

Gnrh Analogue ◽

Tumor Uptake ◽

Prostate Cancer Cell Lines

Introduction: Prostate cancer is a serious threat to men’s health so it is necessary to develop technics for early detection of this malignancy. The purpose of this research was the evaluation of a new99mTc-labeled GnRH analogue as an imaging probe for tumor targeting of prostate cancer. Methods: 99mTc-labeled-DLys6-GnRH analogue was prepared based on HYNIC as a chelating agent and tricine/ EDDA as coligands for labeling with 99mTc. HYNIC was coupled to epsilon amino group of DLys6 through aminobutyric acid (GABA) as a linker. Radiochemical purity and stability in normal saline and serum, were determined by TLC and HPLC methods. Furthermore, calculation of protein-binding and partition coefficient constant were carried out for 99mTc labeled peptide. The cellular experiments including receptor binding specificity and affinity were studied using three prostate cancer cell lines LN-CaP, DU-145 and PC-3. Finally, the animal assessment and SPECT imaging of radiolabeled GnRH analogue were evaluated on normal mice and nude mice bearing LN-CaP tumor. Results: The GnRH conjugate was labeled with high radiochemical purity (~97%). The radiolabeled peptide showed efficient stability in the presence of normal saline and human serum. The in vitro cellular assays on three prostate cancer cell lines indicated that the radiotracer was bound to LN-CaP cells with higher affinity compared to DU-145 and PC-3 cells. The Kd values of 99mTc- HYNIC (tricine/ EDDA)-Gaba-D-Lys6GnRH were 89.39±26.71, 93.57±30.49 and107.3±18.82 in LN-CaP, PC-3 and DU-145 cells respectively. The biodistribution studies in normal mice and LN-CaP tumor-bearing nude mice showed similar results including rapid blood clearance and low radioactivity accumulation in non-target organs. High kidney uptake proved that the main excretion route of radiopeptide was through the urinary system. The tumor uptake was 1.72±0.45 %ID/g at 1h p.i. decreasing to 0.70±0.06%ID/g at 4h p.i. for 99mTc-HYNIC-Gaba-D-Lys6GnRH. The maximum tumor/ muscle ratio was 2.30 at 1h p.i. Pre-saturation of receptor using an excess of unlabeled peptide revealed that the tumor uptake was receptor mediated. The results of the SPECT image of LN-CaP tumor were in agreement with the biodistribution data. Conclusion: Based on this study, we suggest LN-CaP as a favorable cell line for in vivo studies on GnRH analogues. Moreover, this report shows that 99mTc-HYNIC (tricine/EDDA)-Gaba-D-Lys6GnRH may be a suitable candidate for further evaluation of prostate cancer.

Download Full-text