The world's first wiki where authorship really matters (Nature Genetics, 2008). Due credit and reputation for authors. Imagine a global collaborative knowledge base for original thoughts. Search thousands of articles and collaborate with scientists around the globe.

wikigene or wiki gene protein drug chemical gene disease author authorship tracking collaborative publishing evolutionary knowledge reputation system wiki2.0 global collaboration genes proteins drugs chemicals diseases compound
Hoffmann, R. A wiki for the life sciences where authorship matters. Nature Genetics (2008)
 
 
 
 
 

Influence of nicotine, cotinine, anabasine and cigarette smoke extract on human granulosa cell progesterone and estradiol synthesis.

To reveal the well known effect of smoking on the incidence of early abortion, the possible effects of cigarette alkaloids on progesterone and estradiol synthesis were investigated. A suspected cause for early spontaneous abortion is corpus luteum insufficiency. The present experiments evaluate the effects of cigarette smoke alkaloids on progesterone and estradiol biosynthesis. Human granulosa cells were obtained from patients undergoing in vitro fertilization and embryo transfer treatment because of infertility. Incubation of the granulosa cells with cotinine, anabasine, with the combination of nicotine, cotinine and anabasine, or with an aqueous extract of cigarette smoke resulted in inhibition of progesterone synthesis. The alkaloids and smoke extract decreased the DNA content of the culture dish. These latter findings suggested a cytotoxic effect of the alkaloids. Both cotinine and anabasine slightly stimulated the synthesis of normalized estradiol. However, nicotine, combination of all three alkaloids, and cigarette smoke extract had no significant influence on estradiol production. Taken together, these data would suggest that cigarette alkaloids inhibit cellular progesterone synthesis both by inhibiting progesterone synthesis and by causing less specific toxic effects to the cell. In contrast, cigarette smoke alkaloids slightly stimulated or had no effect on estradiol production. These concomitant actions of cigarette alkaloids partly explain the higher incidence of early abortion in pregnant women who smoke.[1]

References

 
WikiGenes - Universities