Sperm capacitation refers to polymerization of filamentous (F)-actin from globular (G)-actin. While the role of ac-tin-related protein 2/3 (Arp2/3) complex in actin polymerization is well appreciated, the underlying mechanism(s) and its relationship with capacitation are poorly understood. Therefore, to evaluate the potential role of Arp2/3 complex on capacitation, bovine spermatozoa were incubated with multiple doses (1, 10 and 100 μM) of CK-636, an inhibitor of Arp2/3 complex with heparin. The cellular localization of the Arp2/3 complex in spermatozoa was identified by immunohistochemistry, whereas western blot was also applied to detect the protein tyrosine phosphorylation of sperm proteins. Additionally, sperm motility and kinematic parameters were evaluated using a computer-assisted sperm analysis system. CK-636 resulted in significant changes in the ratio of Arp2/3 complex localization between acrosome and equatorial region of the spermatozoa. Short-term exposure of spermatozoa to 100 μM of CK-636 significantly decreased sperm motility, however a non-detectable effect on protein tyrosine phosphorylation was observed during capacitation. On the basis of these results, we propose that Arp2/3 complex is associated with morphological changes during capacitation and compromised sperm motility.

The decreased fertility is frequently thought to be problem of cattle production. However, studies figure out that number of these problems is related to bull factors especially in artificial insemination setting. Therefore, this study was designed to investigate the fertility status of bull by their estimated relative conception rate of cows that were inseminated by frozen semen from Korean proven bulls. Here we use the non-return rate (NRR) to access the bull fertility whereas, the NRR was define as the proportion of bulls that semen were used to inseminate cows and the number of cows that did not return for another service within 60 days. The data from 54,388 artificial inseminations (AI) were analyzed from 88 KPN semen. The NRRs of highest and lowest fertile bull were 83.81 and 51.33%, respectively. And mean NRR was 68.27%. In comparison to previously reported study, our data shows 17.38% higher NRR and the absolute value of difference in 50%>NRR and 50%<NRR group was 22.17 and 10.51, respectively (p< 0.001). In conclusion, the decreased fertility might consider as key aspect in achieving considerable conception of cows in existing integrated farming system at Korea.

본 연구는 정자 내의 phsopholipid hydroxide glutathion peroxidase (PHGPx) mRNA 발현 수준, heparin-binding protein (HBP) mRNA 발현 수준, 수태율 그리고 산자수 사이의 관계를 조사하고자 실시하였다. 수태율과 산자수 사이에 있어서 상관관계는 나타나지 않았다. PHGPx mRNA 발현 수준에 있어 산자수가 10두 이상 군에서 (2,414.7±400.7) 8두 미만 군보다 (1,875.8±311.2) 높게 나타났으나 유의적인 차이는 없었다. HBP mRNA 발현 수준에 있어서도 산자수 10두 이상 군에서 (2,255.9±360.8) 8두 미만 군보다 (2,155.4±378.0) 약간 높은 결과를 보였으나, 유의적인 차이는 인정되지 않았다. PHGPx mRNA 발현 수준과 산자수 사이의 관계는 (r=0.206) 정의 상관관계를 보였으나, 유의한 상관관계는 나타나지 않았다. 본 실험의 결과, PHGPx와 HBP의 발현수준이 수태율, 산자수와 유의한 상관관계를 보이지 않았기 때문에 PHGPx와 HBP가 정자의 수정능력을 예측하기에는 미흡한 면이 있다.