Majallah-i Dānishgāh-i ̒Ulūm-i Pizishkī-i Qum (May 2009)
The Effect of Oxamate on LDH-C4 Activity of Sperm in Rats
Abstract
Background and Objectives: LDH-C4 is one of the lactate dehydrogenase isoenzymes found in mature testis and spermatozoa of many species. The Physiological function of these isoenzymes indicates its role in creating energy for sperm motility and survival. In this research, the effects of oxamate as specific inhibitors of the LDH-C4 of rat were studied in vivo. Methods: A total of 20 adult rats were divided into four equal groups. One group as the control group received saline only, and different amounts of oxamate were injected into other three groups (600, 300, 150mg/kg) daily for 45 days intraperitoneally. The rats were then killed with chloroform and the caudal part of epididym was separated. By making several cuts in caudal part of the epididymis, the sperms were isolated and put in T6 medium+5mg/ml -1 BSA. Later, the sperms were incubated under 37ºC and 5% CO2 for one hour. LDH-C4 enzyme was extracted using the Erwin Goldberg and the protein amounts were measured by Lowry's method. Relative purification was done in two stages including ammonium sulfate precipitation and column chromatography by DEAE-Sephadex-A50. All stages of extraction, the amount of total protein, LDH enzyme activity in the oxamate-exposed groups, and specified recipient, were then compared with the control group. Results: In this study, the total enzyme LDH-C4 activity in the control group was 11.8±0.3 and the oxamate recipient groups (150, 300 and 600mg/kg) were 8.3±0.3, 6.9±0.2 and 3.2±0.1 IU, respectively. The concentration of 600mg/kg oxamate was inhibited about 63% enzyme activity compared to control group. Conclusion: This study showed that the oxamate may reduce in vivo enzyme activity through LDH-C4 with increasing concentration and this effect is proportional. Therefore, with the effect of the competitive inhibitors of oxamate on LDH-C4, this substrate can be used as a contraceptive for males.
