ABSTRACT
OBJECTIVE: Polycystic Ovarian Syndrome (PCOS) is the most common endocrine disorder. Chronic anovulation, hyperandrogenism, hirsutism, obesity, infertility and polycystic ovaries (PCO) are clinical hallmarks of PCOS. PCO can be induced in prepubertal rats by daily injection of dehydroepiandrosterone (DHEA). The aims of this study is to investigate cDNA array analysis of genes expressed in the rat PCO induced by DHEA. METHODS: To induce the hyperandrogenic PCO condition, 22-day old rats were injected each day s.c. with DHEA for 15 days. Total ovarian RNA was isolated from the DHEA induced rat PCO and control, and used to prepare radiolabeled cDNA probes, which were hybridized to cDNA arrays. Some of selected genes were further analyzed by reverse transcription-polymerase chain reaction (RT-PCR) or in situ hybridization. RESULTS: Quantitative analysis identified differential expression profiles of 31 genes including leukemia inhibitor factor receptor alpha (LIFR-alpha), alpha 1A adrenergic receptor (ADRA1A), heat shock 90-kDa protein A (HSP90A) and platelet-derived growth factor receptor alpha (PDGFR-alpha) genes. RT-PCR analysis was used to validate the changes in above four gene expressions by the cDNA array. The levels of ADRA1A and LIFR-alpha gene expressions were incresed in DHEA induced rat PCO than control, but HSP90A and PDGFR-alpha gene expressions were decresed in PCO. The mRNA of ADRA1A gene was mainly localized in granulosa cells of cystic follicles. CONCLUSION: Rat hyperandrogenic PCO was induced by daily injection of DHEA for 15 days. ADRA1A, LIFR-alpha, HSP90A and PDGFR-alpha gene expressions were differentially expressed in PCO induced by DHEA. The above four genes may be involved in the mechanism of follicular growth and ovulation processes. The precise relationship between the altered gene expressions and PCO is a matter of further investigation.