Epididymal scanning electron microscopy study in hypothyroid rats

The purpose of this research was to investigate, using scanning electron mi croscopy, the effect of hypothyroidism on the ultrastructure of the rat cau da epididymis. Thyroidectomy was obtained by ip injection of 270 mu Ci of I -131 per rat. One month later, several portions of cauda epididymis were ex amined. Morphological and physiological differences were detected in the ca uda epididymis of the hypothyroid animals when compared to the control norm al rats. The hypothyroid condition was associated with important changes in the luminal surface of the cauda epididymis epithelium. Broken, oblique, a nd loss of stereocilia, denuded epithelial cells, and flattening of the tub ule were observed. The results confirm that hypothyroidism causes marked st ructural changes in the cauda ductus epididymis and could be adversely affe ct sperm maturation motility.