REGENERATION PROCESSES IN RABBIT ENDOMETRIUM - A PHOTODYNAMIC THERAPYMODEL

The origin and process of regeneration in rabbit endometrium was evalu ated following photodynamic epithelial destruction using topically app lied aminolevulinic acid (ALA). Selective destruction of endometrial e pithelium was performed using photodynamic therapy (PDT). ALA was dilu ted to 200 mg/ml dextran 70 shortly prior to administration. A volume of 1.2 ml was injected into the left uterus. Intrauterine illumination (wavelength 630 nm, light dose 40-80 J/cm(2)) was performed 3 h after drug administration. Tissue morphology was evaluated by light and sca nning electron microscopy 1, 3, 7 and 28 days post-treatment (three an imals at each time-point), Regeneration of the endometrium following e pithelial ablation by PDT was fully activated after 24 h and was compl eted after 72 h. Endometrial surface generation occurred by proliferat ion originating primarily in deeper regions of the glands, Findings fr om our morphological follow-up study support the origin of endometrial regeneration being mainly from undifferentiated steal cells and resid ual glandular epithelium.