Correa-Pérez J R, Fernández-Pelegrina R, Zarmakoupis-Zavos P N, Zavos P M
Centro de Fertilidad del Caribe, Torre San Francisco Suite 606, 3659 Ave de Diego, Río Piedras, Puerto Rico 00923.
Andrologia. 2003 Apr;35(2):117-20. doi: 10.1046/j.1439-0272.2003.00542.x.
The use of a protein source such as serum and albumin had been extensively employed as supplements of culture media for handling and culture of gametes and embryos. Protein molecules behave as colloids in solution and contribute to the osmotic pressure of fluids. The interaction of proteins in solution and spermatozoa needs to be assessed in order to determine their possible role in osmoregulation. The aim of this study was to assess possible osmoregulatory mechanisms of protein supplementation against exposure to hypoosmotic conditions by assessing the sperm's response to those environments. A stock hypoosmotic solution (HOS) was prepared by using a mixture of fructose and sodium citrate and adjusted to an osmotic pressure of 150 mOsm l-1. Another stock solution was prepared by diluting a preparation of synthetic serum supplement [SSS; 6% (v/v) total protein] with distilled water to obtain an osmotic pressure of 150 mOsm l-1 (hypoosmotic SSS or H-SSS). Three additional solutions were prepared by mixing the stock HOS and H-SSS solutions in the following proportions (v/v): (i) 75% H-SSS/25% HOS, (ii) 50% H-SSS/50% HOS and (iii) 25% H-SSS/75% HOS. Aliquots of washed spermatozoa from 18 men were diluted 1 : 10 (v/v) with each of the testing solutions and incubated for 60 min. Specimens were assessed on wet mounts for total and specific swelling patterns. Swelling patterns were classified as maximal (>50% tail length swollen) and minimal (<50% tail length swollen) swelling with or without associated sperm motility. The major finding of this study was that increasing the concentration of protein supplementation resulted in a decrease in the proportion of maximal sperm tail swelling patterns and an increase in the proportion of minimal tail swelling patterns. A proportion of spermatozoa which exhibited minimal swelling patterns were still motile in all solutions tested, and the percentage of those spermatozoa increased as the protein supplementation was also increased in the testing solutions. Incorporation of protein supplementation as described in this study delays the effect of sperm swelling in hypoosmotic conditions.
血清和白蛋白等蛋白质来源已被广泛用作配子和胚胎处理及培养的培养基补充剂。蛋白质分子在溶液中表现为胶体，有助于维持液体的渗透压。为了确定蛋白质在溶液中与精子的相互作用在渗透调节中可能发挥的作用，需要对其进行评估。本研究的目的是通过评估精子对低渗环境的反应，来评估蛋白质补充对低渗条件下暴露的可能渗透调节机制。通过使用果糖和柠檬酸钠的混合物制备储备低渗溶液（HOS），并将其渗透压调整为150 mOsm l-1。另一种储备溶液是通过用蒸馏水稀释合成血清补充剂[SSS；6%（v/v）总蛋白]制剂制备的，以获得150 mOsm l-1的渗透压（低渗SSS或H-SSS）。通过按以下比例（v/v）混合储备HOS和H-SSS溶液制备另外三种溶液：（i）75% H-SSS/25% HOS，（ii）50% H-SSS/50% HOS和（iii）25% H-SSS/75% HOS。将来自18名男性的洗涤精子等分试样用每种测试溶液按1:10（v/v）稀释，并孵育60分钟。在湿载玻片上评估标本的总体和特定肿胀模式。肿胀模式分为最大（尾长肿胀>50%）和最小（尾长肿胀<50%）肿胀，伴有或不伴有相关精子活力。本研究的主要发现是，增加蛋白质补充浓度会导致最大精子尾肿胀模式的比例降低，最小尾肿胀模式的比例增加。在所有测试溶液中，表现出最小肿胀模式的一部分精子仍具有活力，并且随着测试溶液中蛋白质补充量的增加，这些精子的百分比也增加。本研究中所述的蛋白质补充可延迟低渗条件下精子肿胀的影响。
