Bone W, Cooper T G
Institute of Reproductive Medicine of the University, Domagkstrasse 11, D-48129 Münster, Germany.
Int J Androl. 2000 Oct;23(5):284-93. doi: 10.1046/j.1365-2605.2000.00243.x.
Chlorinated antifertility compounds are known to inhibit glycolysis of spermatozoa as they reside in the epididymis but new compounds need to be evaluated that retain antifertility action but do not exhibit side-effects. In this study, two known antifertility agents and a related compound were compared for their inhibition of rat sperm metabolism and motility in vitro. The dose-dependent inhibition in vitro of the glycolytic enzymes glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and triosephosphate isomerase (TPI) of distal cauda epididymal rat spermatozoa by (R)-, (S)- and (R,S)-ornidazole (ORN), (R,S)-alpha-chlorohydrin (ACH) and 1-chloro-3-hydroxypropanone (CHOP) was compared. The direct inhibition of GAPDH by ORN suggests that it inhibits without prior conversion outside the cell but inhibition was not stereo-specific. The GAPDH, but not TPI, activity of spermatozoa incubated with ACH and CHOP was highly correlated with kinematic parameters of spermatozoa incubated in pyruvate- and lactate-free medium. ACH only inhibited the activity of intact spermatozoa and the inhibition was not reversed by washing the particulate sperm fraction after sonication. High concentrations of ACH (100 mmol/L) killed intact rat spermatozoa and decreased the extent of GAPDH inhibition. CHOP, unlike ACH, was an effective inhibitor of both intact and sonicated cells. Pre-CHOP, the dimethylketal precursor of CHOP, and its other hydrolysis product MeOH, were both ineffective in vitro. CHOP and related ketals may be more effective inhibitors of sperm glycolysis than ACH and may prove useful for investigating sperm-specific glycolytic inhibition, a prerequisite for the development of antiglycolytic, post-testicular acting contraceptives.
已知氯化抗生育化合物在精子位于附睾时会抑制其糖酵解，但需要评估能保留抗生育作用且无副作用的新化合物。在本研究中，比较了两种已知抗生育剂及一种相关化合物对大鼠精子体外代谢和运动能力的抑制作用。比较了（R）-、（S）-和（R,S）-奥硝唑（ORN）、（R,S）-α-氯甘油（ACH）和1-氯-3-羟基丙酮（CHOP）对大鼠附睾尾远端精子糖酵解酶甘油醛-3-磷酸脱氢酶（GAPDH）和磷酸丙糖异构酶（TPI）的体外剂量依赖性抑制作用。ORN对GAPDH的直接抑制表明它无需在细胞外预先转化即可发挥抑制作用，但抑制作用无立体特异性。与在无丙酮酸和乳酸培养基中孵育的精子运动学参数高度相关的是，与ACH和CHOP孵育的精子的GAPDH活性而非TPI活性。ACH仅抑制完整精子的活性，超声处理后洗涤颗粒状精子部分并不能逆转这种抑制作用。高浓度的ACH（100 mmol/L）会杀死完整的大鼠精子并降低GAPDH的抑制程度。与ACH不同，CHOP是完整细胞和超声处理细胞两者的有效抑制剂。CHOP的二甲基缩酮前体Pre-CHOP及其另一种水解产物甲醇在体外均无效。与ACH相比，CHOP及相关缩酮可能是精子糖酵解更有效的抑制剂，可能对研究精子特异性糖酵解抑制有用，这是开发抗糖酵解、睾丸后作用避孕药的前提条件。
