Myofibroblast-like cells in non-pathological bovine endometrial caruncle

The fine structure of the fibroblastic cells of the normal bovine endometrial caruncle was described. These cells appeared different when compared with the classical fibroblasts encountered throughout the rest of the stromal endometrium. They possess some features similar to those of myofibroblasts reported in various pathological states, to those of epithelioid fibroblasts and to those of cultured fibroblasts. However, they appeared distinct by a few other aspects. We described here the ultrastructure of these particular fibroblastic cells, as they appeared in the caruncle in vivo and under physiological conditions.