The effects of ovarian hormone deficiency on wound contraction in a rat model

Objective To demonstrate the effect of a deficiency of ovarian hormones on the process of wound contraction, using the oophorectomised rat model of the human menopause. Design A randomised controlled trial. Population Ninety-six adult Wistar rats were randomly allocated into either an oophorectomised group or a sham-oophorectomised control group. Methods Having confirmed a significant reduction in plasma oestradiol levels in the oophorectomised rats, full-thickness excised lesions were made in the flank skin of the adult rats at either two weeks or four months after oophorectomy, so that the effects of two different durations of hormone deficiency could be assessed and compared with the sham-oophorectomised controls. Following wounding, the rats were left for 3, 5, 10 or 22 days; wound contraction was assessed from photographs of the wounds taken at these intervals after injury. Results In the rats wounded four months after oophorectomy there was a slower rate of wound contraction, resulting in larger wounds at days 3, 5, 10 and 22, compared with control rats. No significant difference was observed in rats wounded two weeks after oophorectomy, indicating that the effects of ovarian hormone deficiency on this process are delayed. Conclusion Due to the pivotal role of wound contraction in the process of wound healing these findings may be of clinical relevance and could have an important impact on the administration of hormone replacement therapy.