Treatment of normal women with oestradiol plus progesterone prevents the decrease of leptin concentrations induced by ovariectomy
To study the role of oestradiol and progesterone in the secretion of leptin, 21 normally ovulating women were recruited from those scheduled for ovariectomy plus hysterectomy performed in mid-follicular phase of the cycle. Seven of the women were used as controls and received no hormonal treatment post-operatively, Another seven women received oestradiol (oestradiol group) and the remaining seven women received oestradiol plus progesterone (oestradiol plus progesterone group). Serum leptin values showed a temporal but significant increase 24 h after the operation and were significantly correlated with the cortisol and progesterone values, which increased temporarily at 12 h. At that time a marked decline in oestradiol concentrations was seen. After the temporal increase, leptin values in the controls and the oestradiol group decreased significantly up to day 4 (P < 0.05), while in the oestradiol plus progesterone group they increased (P < 0.01) and were significantly higher than in the other two groups (P < 0.05). Body mass index (BMI) was the most important variable accounting for the changes in leptin values post-operatively, but in the oestradiol plus progesterone group progesterone correlated significantly with leptin independently of BMI. These results suggest that progesterone and cortisol can stimulate leptin secretion in women regardless of oestradiol concentrations.