Study Of Gene Expression Profile Of Placenta From Pregnancy Induced Hypertension Using CDNA Microarray

Pregnancy-induced hypertension (PIH) is one of the common complications of pregnancy; but its real cause(s) has been remained unknown after intensive studies for more than a century. By now, the etiology and pathogenesis of PIH still is not understood systematically. Exact role of placenta in PIH has not been investigated penetratingly. Therefore, some novel approaches should be applied to investigate PIH, especially role of placenta in PIH. Some new finding may provide clues to benefit elucidating PIH pathogenesis. ObjectivesTo screen differentially expressed genes in placental tissue of PIH, and further confirm their expression in PIH at the mRNA and protein level respectively, in order to find some candidate genes which might be correlated with PIH pathogenesis. Methods(1) Large scale gene expression profiles in placental tissue of PIH are detected with high throughput cDNA microarray. By comparing with expression of genes in normal placenta, differentially expressed genes in PIH placenta tissue were found. (2) mRNA level of some differentially expressed genes were further confirmed in PIH placenta by semi -quantitative RT-PCR. (3) Part of proteins coded differential expressed genes were detected by tissue microarray combiningwith immunohitochemistry for further confirmation. Results(1) cDNA microarray revealed 393 differentially expressed genes in placental tissue of PIH; 196 genes in them are up-regulated, the other 197 genes are down-regulated. (2) Expression of B-A inhibin was up-regulated significantly in placental tissue of PIH comparing with that of normal pregnancy (P<0.01). Conclusions1. The expression profile of PIH placenta is largely different from that of normal pregnancy; it suggests that placenta has crucial role in PIH pathogenesis.2. P-A inhibin gene is up-regulated significantly in PIH placenta; It may be involved in the pathogenesis of PIH, or result of pathophysiological abnormalities in PIH.3. cDNA microarray is a high throughput tool to screen differentially expressed genes in PIH placenta.4. Tissue microarray, which is a high-throughput and low-waste tool, can be applied to validate differentially expressed genes in large scale at the protein level.