EN
To evaluate the relationship between growth hormone (GH) action and estrogen synthesis in the chicken ovary during food intake disturbance, the expression of GH receptor (GHR) and aromatase mRNAs in the ovary of sexually immature chicken has been examined after short-term starvation. The ovaries were taken from the control (fed ad libitum; n=5), fasted for 24h (n=5) and fasted for 24h+re-fed for 24h (n=5) hens, and the ovarian stroma with primordial follicles and white follicles were isolated. The expression of the examined genes was determined in the ovarian tissues by semi-quantitative RT-PCR. It was found that: (1) GHR and aromatase mRNAs were present in the ovary of immature chickens, (2) the relative level of the GHR gene depended on the ovarian tissues, (3) the fasting caused a significant decrease in GHR and aromatase mRNA expressions in white follicles, and (4) the re-feeding caused an increase in the expression of both the examined genes in white follicles as compared with the fasted chicken. In conclusion, the results obtained indicate that short-term fasting affects GHR and aromatase mRNA expressions in white follicles of immature chickens. Simultaneous changes in the mRNA levels of the examined genes may suggest an involvement of GH in the regulation of aromatase gene expression in the developing ovary of chickens. On the other hand, a decrease in estradiol synthesis may affect GHR expression and GH action within the ovary.