咖啡因对胎鼠及乳鼠睾丸生殖细胞DNA合成影响的体外研究

The effect of caffeine on the DNA synthese of germ cells in testes of fetal and newborn rats in vitro research

目的：了解咖啡因对胚胎及新生时期生殖细胞合成ＤＮＡ的影响及其机制。方法：采用低（０３ｍｍｏｌ／Ｌ）、中（０６ｍｍｏｌ／Ｌ）、高（１２ｍｍｏｌ／Ｌ）浓度咖啡因体外培养ＳＤ孕１８ｄ胎鼠、０ｄ及４ｄ乳鼠睾丸组织块，培养时间分别为１、２、３周，用放射自显影、计算机图像分析的方法观察咖啡因对生殖细胞摄取［３Ｈ］－ＴｄＲ及ＤＮＡ含量的影响。结果：（１）１８ｄ胎鼠、０ｄ乳鼠、４ｄ乳鼠睾丸培养组织内生殖细胞受咖啡因影响依次增加。（２）浓度越高、培养时间越长，咖啡因对生殖细胞影响越明显。（３）生殖细胞数量的减少往往伴随ＤＮＡ含量和［３Ｈ］－ＴｄＲ摄取的降低。结论：高浓度咖啡因长时间培养后使生殖细胞数量减少可能与干扰细胞摄取ＤＮＡ前体物质，降低细胞内ＤＮＡ含量有关。

AIM: To investigate the effect of caffeine on the DNA synthese of germ cells.METHODS:Low (0.3 mmol/L), medium(0.6 mmol/L) and high (1.2 mmol/L) doses of caffeine were used in tissue culture of testicular organ explant taken from 18 days fetal rats, 0 day and 4 days neonatal rats. Autoradiogrophy and computer image analysing were used to observe the -TdR intake and DNA content of germ cells. RESULTS:(1) The effects of caffeine on the germ cells of 18 days fetal testes explant were the least; those on the 0 day were moderate; while those on the 4 days testes were the most. (2) The higher the concentration and the longer the culture time was, the more influence was exerted on germ cells. (3) The decrease of the number of germ cells was accompanied by the decrease of -TdR intake and DNA content in most groups. CONCLUSION:That high doses of caffeine inhibit the proliferation of germ cells after culturing for a long time through intervening the intake of -TdR and decrease the content of DNA.