咖啡碱对椎实螺胚增长的影响

作者采用简单的螺胚生长抑制法,证明软体动物细胞具有DNA复制后修复功能,并受咖啡碱抑制。在没有其他诱变剂的参与下,咖啡碱并不损伤DNA,但也没有保护作用。

EFFECTS OF CAFFEINE ON THE GROWTH OF EMBRYOS IN LYMNAEID SNAILS

Molluscan cells as in other eukaryotic cells Have a post replication repair system which can be inhibited by the presence of caffeine. This is evidenced by the fact that the growth rate of the embryos is slowed down significantly if DNA of embryonic cells during S-phase is damaged by an alkylating agent and subsequently treated with caffeine. But there is no delay of growth rate if DNA is not inflicted and the incubation with caffeine is not long enough. Longterm incubation (15 hrs) with caffeine alone gradually slowed down the growth rate of embryos and eventually arrested mitosis. This may be explained that caffeine raises intracellu-lar c-AMP which inhibits mitoses.Caffeine is still a potential genotoxicant though a few reports regarded it to be nontoxic. It is possible that a portion of damaged cells died and vanished from the population along with their aberrations and mutations.