Llanos M N
Unit of Reproductive Biology, INTA, University of Chile, Santiago.
J Exp Zool. 1994 Aug 1;269(5):484-8. doi: 10.1002/jez.1402690512.
The sperm acrosome reaction (AR) is a crucial step for mammalian fertilization. This work describes experiments to test the effect of the cesium ion (Cs+) and charybdotoxin (ChTX) on the Ca2+ or Na+/K+ ionophores stimulated hamster sperm AR in vitro. Cs+ and ChTX, a polypeptide toxin from the venom of the scorpion Leirus quinquestriatus, are considered blockers of Ca(2+)-activated K+ channels in several somatic cells. Both agents inhibited the AR by 55-66%. The inhibition was completely reversed by the Na+/K+ ionophore nigericin, but not by the Ca2+ ionophore A-23187. Results give evidence in support of a role for Ca(2+)-activated K+ channels in K+ influx required for the occurrence of the hamster sperm acrosome reaction.
精子顶体反应（AR）是哺乳动物受精过程中的关键步骤。本研究描述了测试铯离子（Cs +）和卡律蝎毒素（ChTX）对钙离子载体或钠钾离子载体体外刺激仓鼠精子顶体反应影响的实验。Cs +和ChTX（一种来自五条纹蝎毒液的多肽毒素）被认为是几种体细胞中钙激活钾通道的阻滞剂。这两种试剂都能抑制55%-66%的顶体反应。这种抑制作用能被钠钾离子载体尼日利亚菌素完全逆转，但不能被钙离子载体A-23187逆转。结果表明，钙激活钾通道在仓鼠精子顶体反应发生所需的钾离子内流中发挥作用。
