Laboratory of Animal Reproduction and Development, Graduate School of Agricultural Science, Tohoku University, Sendai, Miyagi, Japan.
Department of Molecular Physiology and Biophysics, Baylor College of Medicine, Houston, Texas, USA.
Anim Sci J. 2022 Jan-Dec;93(1):e13744. doi: 10.1111/asj.13744.
The widely used porcine artificial insemination procedure involves the use of liquid-stored semen because it is difficult to control the quality of frozen-thawed porcine sperm. Therefore, there is a high demand for porcine semen. The control and enhancement of sperm function are required for the efficient reproduction of pigs. We previously reported that gamma-aminobutyric acid (GABA) enhanced sperm capacitation and acrosome reaction in mice. In this study, we demonstrated the presence of GABA receptors in porcine sperm acrosome. Furthermore, we investigated the GABA effects on porcine sperm function. We did not detect any marked effect of GABA on sperm motility and tyrosine phosphorylation of sperm proteins. However, GABA promoted acrosome reaction, which was suppressed by a selective GABA receptor antagonist. GABA binds to GABA receptors, resulting in chloride ion influx. We found that treatment with 1 μM GABA increased the intracellular concentration of chloride ion in the sperm. In addition, the GABA concentration effective in the acrosome reaction was correlated with the porcine sperm concentration. These results indicate that GABA and its receptors can act as modulators of acrosome reaction. This study is the first to report the effects of GABA on porcine sperm function.
广泛使用的猪人工授精程序涉及使用液态储存的精液，因为很难控制冷冻解冻猪精子的质量。因此，对猪精液的需求很高。为了实现猪的高效繁殖，需要控制和增强精子功能。我们之前报道过，γ-氨基丁酸（GABA）可增强小鼠精子获能和顶体反应。在这项研究中，我们证明了 GABA 受体存在于猪精子顶体中。此外，我们研究了 GABA 对猪精子功能的影响。我们没有发现 GABA 对精子运动和精子蛋白酪氨酸磷酸化有任何显著影响。然而，GABA 促进了顶体反应，而选择性 GABA 受体拮抗剂则抑制了顶体反应。GABA 与 GABA 受体结合，导致氯离子内流。我们发现，用 1μM GABA 处理可增加精子内氯离子的浓度。此外，在顶体反应中有效的 GABA 浓度与猪精子浓度相关。这些结果表明，GABA 及其受体可以作为顶体反应的调节剂。这项研究首次报道了 GABA 对猪精子功能的影响。
