Using rats as a research model for the study of endometriosis.

Although there are disadvantages of extrapolating data across species, the rat model may be used to study events involved in the pathogenesis and pathophysiologies of endometriosis or novel therapeutic approaches for this disorder that are not accessible in humans. Rat endometriotic tissues are similar to human lesions in vivo, and rat endometriotic tissues and cells perform in a similar manner as human endometriotic tissues and cells in organ explant culture and isolated cell culture. The rat model permits studies of mechanisms and regulators in a controlled manner free from confounding influences such as individual patient variation and environmental influences. The primary method used for induction of endometriosis in rats has been autotransplantation of uterine squares (implants) into the peritoneal cavity. Beyond mere growth of endometrium in ectopic locations, rats with endometriosis display similar symptoms, including a reduction in fertility and fecundity, and the endometriotic implants react similarly to therapeutics as those of humans with the disease. Similar alterations in gene expression and protein production have been observed in endometriotic tissues from rats and humans that may, in part, be causative agents involved in the pathogenesis or pathophysiologies of endometriosis.