An ultrastructural study of the effects of gossypol on the endometrium of the female rat.

Abnormal desmosomes were found in the endometrial epithelial cells of rats treated orally with gossypol acetic acid at a dose of 60 mg/kg/day for 30 days. Desmosomes in the endometrium of rats treated at 40 mg/kg/day were similar to those of controls. Abnormalities included an increase in desmosome number with prominent filamentous interconnections, asymmetry, disorganization of tonofilaments, missing tonofilaments, missing desmosomal plaques that did not appear to line up with those of the adjacent cell. It is thought that the antifertility actions of gossypol may be due to a disturbance of desmosome formation. This would cause a disruption of endometrial cell adhesion as well as an alteration in the microenvironment within cytoplasmic domains. These changes could lead to an endometrial environment unfavorable to fetal development.