220. Equine growth hormone enhances motility and extends longevity of ram spermatozoa in vitro

2005 ◽  
Vol 17 (9) ◽  
pp. 85 ◽  
Author(s):  
B. J. King ◽  
V. V. Da Silva ◽  
J. D. Harper ◽  
C. J. Scott ◽  
M. N. Sillence
Keyword(s):  
Growth Hormone ◽  
Dilution Rate ◽  
Sperm Motility ◽  
Room Temperature ◽  
Final Concentration ◽  
Bovine Growth Hormone ◽  
Semen Preservation ◽  
Sperm Survival ◽  
Motility Of Sperm

Sperm survival in vitro decreases with time at room temperature, but may be improved by treatment with recombinant bovine growth hormone in rats1, bulls2 and horses3. Two experiments investigated the effect of equine growth hormone (eGH) on the longevity of ram spermatozoa in vitro. The aim of experiment 1 was to determine if the addition eGH would improve the motility of ram spermatozoa after 24 h and identify any interaction with semen dilution rates used for ram semen preservation. Semen was collected from five mature Merino rams. Ejaculates were assessed for good quality and were diluted 1+50, 1+4, 1+3, 1+2 (semen+diluent) with a Tris-based cryoprotectant. Aliquots from each ram were mixed with eGH to achieve a final concentration of 100 ng/mL eGH and stored at 20°C for 24 h. Motility of spermatozoa was then assessed manually. eGH improved the motility of spermatozoa at all dilution rates compared to controls (P < 0.0001) but most markedly in the 1 + 3 and 1 + 2 samples (42.6 ± 0.8% eGH v. 22.7 ± 2.6% control; 40.5 ± 1.4% eGH v. 22.7 ± 2.2% control, respectively, P < 0.01). The aim of experiment 2 was to determine the optimum eGH concentration for improving sperm motility. eGH was added to aliquots of diluted semen (1+3 dilution rate) to produce samples with final concentrations of 1000, 100, 10 and 1 ng eGH/mL. The samples were placed in a water bath at 20°C for 24 h at which time the motility of sperm was assessed as before. Sperm motility was higher in the 100 ng/mL eGH sample (P < 0.05; 39.6 ± 0.7%) compared to other concentrations (1000 ng/mL 11.8 ± 0.7%, 10 ng/mL 21.5 ± 0.7% and 1 ng/mL 11.3±0.7%). We conclude that growth hormone is effective in promoting the longevity in vitro of ram spermatozoa stored at room temperature, and that this effect is concentration dependent. (1)Breier et al. (1996). Endocrinology 137, 4061–4064.(2)Sauerwein et al. (2000). Dom. Anim. Endocrinol. 18, 145–158.(3)Champion et al. (2002). Theriogenology 57, 1793–1800.

107 COMPARISON OF PRIMATE SPERM CRYOPRESERVATION PROTOCOLS: POST-THAW SPERM RECOVERY AND HYPERACTIVATION IN CULTURE

2006 ◽  
Vol 18 (2) ◽  
pp. 161
Author(s):  
S. Nichols ◽  
B. Bavister
Keyword(s):  
New York ◽  
Sperm Motility ◽  
Room Temperature ◽  
Vitro Fertilization ◽  
Treatment Groups ◽  
Motility Of Sperm ◽  
Fertilizing Capability ◽  
Over Time

Cryopreservation of spermatozoa provides material for gene banking of genetically valuable males and offers convenience for in vitro fertilization (IVF). In addition, cryobanking of spermatozoa allows less frequent ejaculation collections from males. The present study compared the effectiveness of several published techniques in non-human primates to find the most efficient one for rhesus macaque (Macaca mulatta) semen cryopreservation. The effectiveness of each method was assessed by longevity (post-thaw motility % and duration) and ability to hyperactivate in culture in response to chemical activators (caffeine, dbcAMP) needed for rhesus sperm capacitation (Boatman and Bavister 1984 J. Reprod. Fertil. 71, 357-366). The ability to hyperactivate provides a reasonable assessment of the fertilizing capability of spermatozoa prior to performing IVF; the latter was impractical for this study, given the large number of treatments and endpoints. Spermatozoa were collected via electroejaculation from one male on three occasions to avoid confounding treatments with male effects. Each ejaculate was divided into one of four treatment groups for cryopreservation: Method A (Seier et al. 1993 J. Med. Primatol. 22, 355-359); Method B (Wei et al. 2000); Method C (Sanchez-Partida et al. 2000, Biol. Reprod. 63, 1092-1097); and Method D (Isachenko et al. 2005 Reprod. Biomed. Online 10, 350-354). Protocols were followed according to each published technique. Upon thawing, each sample was split into different incubation conditions: 37�C, 5% CO2 in air or room temperature for 0-24 h. One dose of activators was used according to standard protocol. Statistical analyses of motility rates were performed using 2 � 2 G tests (Sokal and Rohlf 1981 Biometry. New York: W. H. Freeman Co.) to determine significance. Samples cryopreserved using method D did not survive the method (motility = 0) and were not included in the statistical analysis. Methods A-C all demonstrated reasonable post-thaw motility recovery rates (68%, 73%, and 62%, respectively) and underwent capacitation within 30 min of exposure to activators. Sperm motility decreased over time in culture within each treatment at 37�C. However, spermatozoa in Method A were significantly less motile at 4 and 24 h than those in Methods B and C, and Method B spermatozoa were significantly less motile at 24 h than those in Method C. Sperm motility also decreased over time in samples incubated at room temperature, with motility of sperm in Method A motility being significantly less at 24 h than that of sperm in Methods B and C. Method C best preserved motility over time regardless of temperature of incubation upon thawing. Overall, incubation at room temperature preserved motility better than incubation at 37�C. Methods A-C yielded satisfactory post-thaw recovery of progressively motile spermatozoa despite the various differences among their protocols. For long-term use of each sample, however, it would be beneficial to incubate spermatozoa at room temperature after using Method C. This technique appears to be more appropriate for gene banking rhesus semen, and applying this protocol would allow more efficient usage of each semen sample, potentially providing for multiple IVF cases over a 24-h period. This work was supported by NIH Grant RR15395.

ANALYSIS OF THE BIPHASIC ACTION OF GROWTH HORMONE IN VITRO ON THE RAT DIAPHRAGM

1968 ◽  
Vol 57 (3_Suppl) ◽  
pp. S19-S35 ◽  
Author(s):  
Å. Hjalmarson
Keyword(s):  
Growth Hormone ◽  
Actinomycin D ◽  
Accumulation Rate ◽  
Inhibitory Effect ◽  
Bovine Growth Hormone ◽  
Rat Diaphragm ◽  
Dual Nature ◽  
Hypophysectomized Rats ◽  
D 20

ABSTRACT In vitro addition of bovine growth hormone (GH) to intact hemidiaphragms from hypophysectomized rats has previously been found to produce both an early stimulatory effect lasting for 2—3 hours and a subsequent late inhibitory effect during which the muscle is insensitive to further addition of GH (Hjalmarson 1968). These effects on the accumulation rate of α-aminoisobutyric acid (AIB) and D-xylose have been further studied. In presence of actinomycin D (20 μg/ml) or puromycin (100 μg/ml) the duration of the stimulatory effect of GH (25 μg/ml) was prolonged to last for at least 4—5 hours and the late inhibitory effect was prevented. Similar results were obtained when glucose-free incubation medium was used. Preincubation of the diaphragm at different glucose concentrations (0—5 mg/ml) for 3 hours did not change the GH sensitivity. Addition of insulin at start of incubation could not prevent GH from inducing its late inhibitory effect, while dexamethasone seemed to potentiate this effect of GH. Furthermore, adrenaline was found to decrease the uptake of AIB-14C and D-xylose-14C in the diaphragm, but not to change the sensitivity of the muscle to GH. Preincubation of the diaphragm for 3 hours with puromycin in a concentration of 200 μg/ml markedly decreased the subsequent basal uptake of both AIB-14C and D-xylose-14C, in the presence of puromycin, and abolished the stimulatory effect of GH on the accumulation of AIB-14C. However, the effect of GH on the accumulation of D-xylose-14C was unchanged. The present observations are discussed and evaluated in relation to various mechanisms of GH action proposed to explain the dual nature of the hormone.

scholarly journals Metabolic effects of the major component of bovine growth hormone

1971 ◽  
Vol 122 (5) ◽  
pp. 633-640 ◽  
Author(s):  
N. I. Swislocki ◽  
M. Sonenberg ◽  
M. Kikutani
Keyword(s):  
Growth Hormone ◽  
Deae Cellulose ◽  
Heterogeneous Material ◽  
Parent Material ◽  
Metabolic Effects ◽  
Sedimentation Equilibrium ◽  
Bovine Growth Hormone ◽  
Hormone Effects

Bovine growth hormone, subjected to DEAE-cellulose chromatography, yielded one major and several minor components. The various chromatographic fractions of bovine growth hormone were compared with the parent material for their ability to promote hormone effects in vivo and in vitro. The major component of bovine growth hormone was homogeneous by acrylamide-gel electrophoresis, rechromatography and sedimentation equilibrium. Its amino acid composition was similar to that of the parent hormone. The major component possessed all the qualitative activities present in the original heterogeneous material, including promotion of acute hypoglycaemia and hypolipaemia. In studies in vitro in adipose-tissue segments the major component of the hormone increased entry of glucose and its oxidation to CO2, conversion of glucose into glyceride glycerol, release of glycerol and incorporation of histidine into adiposetissue protein. Other chromatographic fractions of bovine growth hormone were not homogeneous and possessed some but not all of the metabolic activities attributed to the hormone preparations or its major component. Thus, the metabolic effects obtained with bovine growth-hormone preparations in vivo and in vitro can be obtained with the major homogeneous component of the hormone. This observation precludes the possibility that the metabolic effects obtained with bovine growth-hormone preparations are due to the combined actions of a number of components found therein.

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