• Animal cells and systems
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• 제4권2호
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• pp.151-155
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• 2000

Nitric oxide (NO) is a reactive free radical which plays important roles in animal physiology. To investigate involvement of NO in acrosome reaction (AR), effects of drugs which modulate the intracellular NO level were examined in mouse spermatozoa. N (G)-nitro-L-arginine (L-NA), a potent inhibitor of NO synthesis, decreased AR in a reversible manner, On the other hand, sodium nitroprusside (SNP), an NO generating agent, increased spontaneous AR. Preincubation of sperm in the presence of L-NA potentiated AR after sperm transfer into plain- or SNP-media. Methylene blue, a NO scavenging agent, decreased spontaneous AR. Taken together, it is concluded that NO positively controls AR.

• Reproductive and Developmental Biology
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• 제34권3호
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• pp.241-246
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• 2010

The objective of this study was to investigate the effect of storage time on fresh boar semen in Androhep and Beltsville Thawing Solution (BTS). Boar semen samples extended in each extender were stored at $17^{\circ}C$ up to 4 days. Sperm motility kinematics was evaluated by computer assisted sperm analyzer (CASA) and capacitation status by chlortetracycline (CTC)/Hoechst 33258 staining. Sperm motility (%) was not decreased during storage in BTS and Androhep. No significant difference between extenders was observed. Only significant differences in kinematic parameters on linearity during storage were found. The percentage of dead sperm significantly decreased during storage (p<0.05). Also the percentage of noncapacitated, capacitated, and acrosome-reacted sperm significantly modified during storage (p<0.05). However, there was no significant difference between extenders except proportion of capacitated sperm. This finding supported that modification in these parameters was not significantly different between extenders during this short-term storage. Our finding strongly indicated that both Androhep and BIS maintained favorable conditions for motility, motility kinematics, and capacitation status during short-term storage. Despite modifications in some parameters were apparent during sperm storage in extenders, these may not affect the fertilizing capacity of boar semen.

• Reproductive and Developmental Biology
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• 제35권1호
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• pp.47-54
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• 2011

Endocrine disruptors bind to hormone receptors on sperm membrane, therefore spermatozoa are potentially a useful model for examining estrogenic activities of endocrine disruptors. The objective of this study was to compare the effects of two xenoestrogenic compounds [genistein (Gen) and 4-tert-octylphenol (OP)] to those of two steroids [estrogen ($E_2$) and progesterone ($P_4$)] on boar sperm % motility and motion kinematics of in vitro. Porcine spermatozoa were incubated with various concentrations ($0.001{\sim}100\;{\mu}M$) of each chemical for 15 or 30 min, and then assessed % motility and sperm motion kinematics using computer assisted sperm analyzer (CASA). Each chemical decreased sperm % motility, and OP decreased VSL and VAP compared with untreated control(p<0.05). $E_2$ stimulated the motion kinematic changes except VCL. Moreover, Gen had effects on VCL and VAP alterations after 30 min incubation. In summary, since all chemicals studied effectively altered sperm % motility and motion kinematics, it was concluded that porcine spermatozoa could be a useful model for in vitro screening of potential endocrine disruptors.

• Reproductive and Developmental Biology
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• 제29권3호
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• pp.193-199
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• 2005

인간의 불임을 극복하기 위한 번식공학 기술의 효율성을 증가시키기 위해 성세포의 동결이 널리 수행되고 있으나 동결 기술의 효율성에 있어서 논란의 여지가 있다. 본 연구에서는 체외수정란을 생산하기 위한 난자세포질내 정자미세주입(ICSI) 시술에 사용되는 정자와 이들 기술을 이용 생산한 체외수정란의 동결이 배 발생 및 임신에 미치는 효과를 조사하였다. ICSI방법으로 체외수정란을 생산하는 경우 정자의 동결이 체외수정, 발생 및 임신에 영향을 미치지 않았으며, 특히 동결융해한 사출 및 정소정자에 의한 체외수정율과 발생율 및 임신율도 차이가 없었다. 한편 체외수정란을 동결하는 경우 완만동결과 초자화동결에 의한 체외수정란의 생존율과 임신율은 차이가 없었으나, 동결수정란은 신선수정란에 비하여 임신율이 유의하게 낮았다(p<0.05). 결론적으로 ICSI에 사용되는 정자와 달리 ICSI에 의해 생산된 수정란을 동결하는 경우 임신율을 저하시킬 수 있다.

• Reproductive and Developmental Biology
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• 제29권3호
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• pp.141-144
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• 2005

This experiment was to investigate whether the mitochondria function assessment can be used for the prediction of sperm fertility through examining the correlation between mitochondria fluoromicroscopic frequency of frozen-thawed eight Hanwoo bull semen using rhodamine123 (R123) and in vitro embryo development following fertilization. Individual sperm were stained in 5 ${\mu}g/mL$ R123-added calcium-free Sp-TALP for 30 min at 0 h, 6 h, 12 h and 24 h after thawing and examined their mid-piece under an epifluorescence microscope using 495 nm excitation filter (x1,000). Three replications were taken, and at least 300 sperm per individual were examined. When semen samples were separated into two groups (good and poor) by sperm motility and fluorescent frequencies at just after thawing, average fluorescent frequencies were remarkably reduced as time going (0 h; $53.29{\~}72.94\%$, 6 h; $21.40{\~}58.90\%$, 12 h; $8.26{\~}25.93\%$, 24 h; $1.00{\~}13.78\%$, irrespective of selected group, and there were no differences at 6 h or 12 h after thawing between selected groups but indicated significant difference at 24 h after thawing (p<0.05). In vitro fertilization rates in good and poor groups ranging $70.8{\~}77.8\%$ and $52.1{\~}84.5\%$, respectively, were not significantly different. However, in vitro development rates of the same groups ranging $25.7{\~}40.0\%$ and $12.9{\~}1.8\%$, respectively, were significant different (p<0.05). These results demonstrate that mitochondria fluoromicroscopic assessment of frozen-thawed bovine sperm may be used as a criterion to select more fertile sperm.

• Reproductive and Developmental Biology
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• 제35권3호
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• pp.265-271
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• 2011

This study was undertaken to find out the effect of methyl-beta-cyclodextrin (MBCD) on cold shock and membrane cholesterol quantity of sperm during the freezing process in miniature pigs. For this study, semen ejaculated from PWG M-type miniature pig was diluted that freezing solution (with egg yolk group) and m-Modena B (without egg yolk group) treated with 0, 1, 5, 10 and 20 mM MBCD before freezing process. The diluted semen was monitored sperm ability at room temperature, after cooled until $5^{\circ}C$ and after forzen-thawed for cold shock test of spermatozoa. Also, membrane cholesterol of sperm was extracted by folch solution at the same time sperm ability was assessed for viability and acrosomal status. The membrane cholesterol quantity was measured by thin-layer chromatography (TLC) method. The result, viability and acrosome integrity in semen diluted without egg yolk groups were decreased at all temperature range by increasing of MBCD concentration. In particular, sperm of egg yolk group was showed that significantly higher viability and lower acrosome damage when treated with 5 mM MBCD (p<0.05). The results of TLC experiment, cholesterol amounts were increased with MBCD cocentration in egg yolk, and decreased with MBCD concentration in m-Modena B. In cryopreservation efficiency, there was no significant difference at viability, and acrosomal state of sperm in 5 mM MBCD concentration was significantly lower in acrosome damage than other groups (p<0.05). Therefore, the addition MBCD in egg yolk was protected spermatozoa from cold shock injury. This protective effect of MBCD may be due to addition of sperm membrane cholesterol.

• Reproductive and Developmental Biology
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• 제35권4호
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• pp.435-439
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• 2011

Sildenafil citrate (SIL) a phosphodiesterase 5 inhibitor (PDE5I) has been used for long time as a first line oral drug for erectile dysfunction. Though it has beneficial effects on erectile organ it also has some adverse effects in other cells and/or tissues related to reproductive system when exposed to longer duration. The objective of the present study is to evaluate the long term effect of SIL on sperm parameters in Wistar albino rat. The animals are divided into two groups, for group I - rats were treated with saline (vehicle alone) and group - II oral administration of 5 mg/kg b.w. of SIL was administrated orally once in a day for 120 days. At the end of the trial period animals were sacrificed and epididymal sperm were subjected to various analysis. Results showed significant reduction in sperm count, motility, viability and morphologically intact sperm in long term PDE5I exposed animals when compared to control. Acrosomal status and fertility test also showed significant reduction in long term PDE5I exposed animals. The present study clearly indicated that long term SIL has shown to induce alteration in sperm quality and quantity, leading to decline in fertility rate. Indicate that SIL impinge on spermatogenesis as well as epididymal function. Understanding the molecular down-stream events involved in long-term exposure to PDE5 inhibitor can be valuable to supervise on related infertility issues and to suggest corrective measures.

• Reproductive and Developmental Biology
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• 제28권4호
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• pp.261-265
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• 2004

The present study was conducted to assess sperm characteristics in miniature-pig. The semen samples were transported to the laboratory at 17℃ within 3 hours after collection. The extended semen was stored at 17℃, and sperm quality was evaluated at 0, 1, 3, 5 and 7 days after storage. The semen volume of miniature-pig (62±22㎖) was significantly (p<0.05) lower than that of Duroc (155±25㎖) and Yorkshire (154±23㎖). Significant differences were also observed in sperm concentrations. During 3 days of storage, sperm viability did not differ among miniature-pig, Duroc and Yorkshire. However, the viability was significantly (p<0.05) lower in miniature-pig than in Duroc and Yorkshire semen after Day 3 of storage. In abnormality, acrosome intactness and intensity, there were no differences among miniature-pig, Duroc and Yorkshire semen. On the other hand, the viability of frozen-thawed sperm in miniature-pig was significantly (p<0.05) lower than in that of Duroc and Yorkshire. This study also examined CTC patterns in frozen-thawed spermatozoa. The rates of AR pattern were higher in miniature-pig than in Duroc and Yorkshire. However, no difference was found in F, B and AR patterns. The results of present study suggest that further research is necessary to develop of semen extender and freezing methods to improve sperm quality in miniature-pig.

• Reproductive and Developmental Biology
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• 제29권4호
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• pp.247-252
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• 2005

The purpose of this study was to assess sperm quality during in vitro storage of miniature-pig semen in order to determine which extender should be used and how extender can be diluted for in vitro storage of miniature-pig semen. Freshly ejaculated miniature-pig's semen was diluted with same volumes of Beltsville Thawing Solution (BTS), Androhep, Modena, Mulberry III and modified-Modena extenders. Sperm quality was evaluated by examining viability, motility, abnormality, acrosome intactness, intensity and capacitation status by chlorotetracycline (CTC) staining. Sperm motility decreased with storage period prolonged and differences among BTS, Androhep, Modena and Mulberry III were apparent On Day 1, approximately 80% of the sperm were motile, but motility decreased to $40\%$ at Day 7. During the 7 days of storage, sperm survival in modified-Modena B extender was higher than another extenders. However, it was not differ significantly among other extenders. The percentage of F and B patterns were not differ significantly among the extenders. However, F pattern in modified-Modena B extender was slightly higher until 3 days of storage than that of Modena extender, modified-Modena A extender and modified-Modena C extender. The percentage of AR patterns in modified-Modena B extender was slightly lower, but did not differ significantly among other extenders. The results of present study suggest that modified-Modena B was effective as new extender for in vitro storage of miniature-pig semen.

• Clinical and Experimental Reproductive Medicine
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• 제45권1호
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• pp.17-24
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• 2018

Objective: To investigate sperm chromatin/DNA integrity, global DNA methylation, and DNMT mRNA transcription in men with oligoasthenoteratozoospermia (OAT) compared with normozoospermic men. Methods: Semen samples from 32 OAT patients who comprised the case group and 32 normozoospermic men who comprised the control group were isolated and purified using a standard gradient isolation procedure according to World Health Organization criteria. DNMT1, DNMT3A, and DNMT3B transcripts were then compared between groups using real-time quantitative reverse-transcription polymerase chain reaction. Global DNA methylation in sperm was determined by an enzyme-linked immunosorbent assay. Protamine deficiency and the proportion of apoptotic spermatozoa were evaluated using chromomycin A3 (CMA3), aniline blue (AB), and toluidine blue (TB) staining, as well as the terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay. The p-values < 0.05 were considered to indicate statistical significance. Results: Significantly higher proportions of AB+, TB+, CMA3+, and TUNEL+ spermatozoa, as well as DNMT3A and DNMT3B transcription, were found in the OAT group. Positive correlations were detected between sperm parameters, DNA/chromatin damage, and DNMT3A and DNMT3B transcripts. Global DNA methylation was significantly higher in the OAT patients and had a significant correlation with abnormal results of all sperm chromatin integrity tests, but was not associated with DNMT1, DNMT3A, or DNMT3B expression. Conclusion: Oligoasthenoteratozoospermic men showed abnormal sperm parameters, abnormal chromatin/DNA integrity, and a higher global DNA methylation rate, as well as overexpression of DNMT mRNA.